Re: anyone interested in a small game?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 seems to be pretty similar to asteriods. we can just do an engine that can do both. at the same time. does clojure support remote agents? Am 31.10.2011 12:41, schrieb Timothy Baldridge: I'd be up for something like this. I have a fair amount of clojure experience, and I've done quite allot of work with OpenGL in other languages, so this actually sounds fun! Another option to consider, is the old DOS version of SpaceWar! http://www.youtube.com/watch?v=yY5qHe2VadA I like the idea of doing a Asteroids/Spacewar! clone, mostly because it would give us a chance to introduce Agents as the building block of the game engine. Timothy On Sun, Oct 30, 2011 at 1:32 PM, Dennis Haupt d.haup...@googlemail.com wrote: hi community, i decided to create a (small) game in clojure to get a bit of non-theoretical experience. i'm pretty much a clojure noob (only did a few experiments) but have done a few real things in scala - which is totally awesome btw - so i do have some functional programming experience. if there's someone here who would like to join, just do so by answering yes or something like that. i was thinking about a game like asteroids, tower defense or that old game with lots of aliens on the top and two players at the bottom, shooting upwards. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOrpI5AAoJENRtux+h35aG4TYQAI/fKfaddP0UAotFk44WekQs joW3ea7v84rcg6qsCgQe0by0Zsa+oYP2nlQ4lneTu9VT4JQHC3MpLesRVYQ3qLQv 7VrBvuifLb84UeHWZhlYflMApVDr0l200anaHEhXbgxbG38MR0oBsAVg6wP5gx6a TW17BSAIPEmu4XqMQxD9yYJvJMoMsKwDrA2Yguj7/hgJh3znNlADZZ6JVqKMv6h3 IyyYkDaYBJNAAhZiEm8zV1BVgzA6Lyh/IgBCWg2/o2oq4OkcjL2UBd2suvRO/gVS 24bBJoPHn+w2XVaplBWsxF/lEPnogOo9CeK5MOnaTVIA2Jq0e6cCnSM30OSsQ5UU 2kdnU6dOZ6VNocfL80T5b2eFvTjQKU6k3GIPV03FP6LxvRT8g/y5qqecTYlBW7G2 KJXY0Xw7otHQcaQxQD4kF//FCyim2+bQj5i//MhKzeMGRLr6CE8fSgov2nmwd6M8 yuCdip7bzOEsw2Bzr4iiC1dTp3pZhqLSIeDUJgFCI35argB4rai0RKne0eTly1fj 1jaQKddTY1mDrPKKsuKSwVAxFj6LeVHnBrdyzIr/9fEC/ccThIB8HoZmHbGU4jOZ EwU9rCGNyd/lY1AcA6ou1MR2YY+MtlTmep7gczUHwelAsqbBxK3HS/2puPgQuOl+ 8J+pEDcccpqAXRCKRSrp =z8nu -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: anyone interested in a small game?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 isn't openGL a bit of overkill (we can just use java2d), or do you want to add a renderer doing all sorts of awesome stuff which totally contradicts the white-polygon-on-black-background graphics? might give the game a pretty unique look :) Am 31.10.2011 12:41, schrieb Timothy Baldridge: I'd be up for something like this. I have a fair amount of clojure experience, and I've done quite allot of work with OpenGL in other languages, so this actually sounds fun! Another option to consider, is the old DOS version of SpaceWar! http://www.youtube.com/watch?v=yY5qHe2VadA I like the idea of doing a Asteroids/Spacewar! clone, mostly because it would give us a chance to introduce Agents as the building block of the game engine. Timothy On Sun, Oct 30, 2011 at 1:32 PM, Dennis Haupt d.haup...@googlemail.com wrote: hi community, i decided to create a (small) game in clojure to get a bit of non-theoretical experience. i'm pretty much a clojure noob (only did a few experiments) but have done a few real things in scala - which is totally awesome btw - so i do have some functional programming experience. if there's someone here who would like to join, just do so by answering yes or something like that. i was thinking about a game like asteroids, tower defense or that old game with lots of aliens on the top and two players at the bottom, shooting upwards. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOrpwDAAoJENRtux+h35aGBx4P/RXFWjr+zFQMjA49bHobnOKY PbepwqpwunucJ9M6zp0MDnudoXWDyE2zCG7QgAf/ZgaSoI4+4KvRL5IwYgPwBDO2 rgAEMSyK30/HLnSnn5zgTrFRRTNde2oCFMB5soE5qYNvRKB0lXJ58DbKHF3f21H9 NXPwz4x6GU1Vs1w9Kx94Skx+Rf4mJKX7sN6choI8ENOE8dEiXiyTFdqO1cNjPZyR iimmEhaXzwjkHCcCPiLo1rTSn14yNty0EObNvo/WhFqK/4Y3YP7NR9tWrHJSN5ll Sc4n9+B+qpaHrun+QvjIE41vXaMF3LPrXLRM9tM042ImRdvy210eVBU5h1riGA97 R/0c9fm6L4UbeuhS/SBVEg3m9bdL62dcxOmDcYi0kuYrNRRcBbioptEYCxiyhcmy bna6/k6UZX+YeLNtvXBk49+K2fQElC3TIzEmIkotMd3Q0gjhhSsoYgcW3uCvWLy1 0RNSPSmKmQ9m6Htif/yO2dCnCVadO/nJgqeE8LsDMhtLlh8gj4Q+x3ppU6cxtiEP S9mGISRv6Sk6p88TVHZGVKXEHLaRuhWrfC0Nu1mTQQEwm3ilQ10ipSLrnvlGfvBs eqCqVJpXtx/m6cvtLLczB3WoKpsGvLhDJMq0TFxYMIKbws726YdpN/VRaEMSkGFm YJWqDYGOPOubGge4tJbn =JTgF -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: anyone interested in a small game?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 one agent per entity? i'd have done an agent for the whole world and apply functions like apply-collision and apply-shot-fired to it Am 31.10.2011 14:46, schrieb Timothy Baldridge: Haha! I forgot about Java2d... Yeah, that would work just fine. No, Clojure does not support remote agents. But agents can really help in a system like this to express objects as distinct entities. That is, you have one object per item on the screen, and then each object basically can live on its own: (send entity update-time timespan) (send asteroid do-split) etc. Actually, this really isn't too long of a project, at least the asteroids part isn't. Timothy On Mon, Oct 31, 2011 at 8:00 AM, Dennis Haupt d.haup...@googlemail.com wrote: isn't openGL a bit of overkill (we can just use java2d), or do you want to add a renderer doing all sorts of awesome stuff which totally contradicts the white-polygon-on-black-background graphics? might give the game a pretty unique look :) Am 31.10.2011 12:41, schrieb Timothy Baldridge: I'd be up for something like this. I have a fair amount of clojure experience, and I've done quite allot of work with OpenGL in other languages, so this actually sounds fun! Another option to consider, is the old DOS version of SpaceWar! http://www.youtube.com/watch?v=yY5qHe2VadA I like the idea of doing a Asteroids/Spacewar! clone, mostly because it would give us a chance to introduce Agents as the building block of the game engine. Timothy On Sun, Oct 30, 2011 at 1:32 PM, Dennis Haupt d.haup...@googlemail.com wrote: hi community, i decided to create a (small) game in clojure to get a bit of non-theoretical experience. i'm pretty much a clojure noob (only did a few experiments) but have done a few real things in scala - which is totally awesome btw - so i do have some functional programming experience. if there's someone here who would like to join, just do so by answering yes or something like that. i was thinking about a game like asteroids, tower defense or that old game with lots of aliens on the top and two players at the bottom, shooting upwards. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOrrKfAAoJENRtux+h35aG8xMP/RNYGqwEAXbuovpdI1KDyiny fxUTQc+cppQwDNl43OwkdHlqlj7hHoWZVSshd5GoKjTBGGU/H6McILD0mKCvGUPw EMOSDdzORPEJkQFc/VINGzBW3veQwAy/3K6TujwyO6ChsSCGbBepSABVvAtdUHpM xU9CkSCu2s5iwxO25CrlsTliwV6xAAwUUkM0Rp7AR+qYco5msOPLBG0+KU/XVIPO hqRX82SaqifPAbk2Yx4vRoR5wamF0w4vd0rRMVENMckImI3DteX1To+k3hHwCvLt GJKyHwJXZRJ0JzBzUITjqfuVUI9pW+71RBh5odb13PuDNOpRou/k/JgDeTXK6e8t l1BKpbchs+ar1IO38mlWSvsVwYDySuzkopBH1cSgOyAgUa1Yi/0HNSA05BgXxlyZ voGnTGBjis/eLZ2Bdbz3EgITetxG/ypM41hlIj0QHEX6JWiAP9tCq7xvTLUVQ0a4 zzt+knoDOatQwbn+TgtcYyfl8ObtVrMJaQhpY5PnpdN3MDXFVqJpIZ8urm2UAn9w 35V+SiIV3/1UOAVaEdzmCLhDMPcHCuuB09rWZ7QpcywnomDyoGmURcog7hZX64hJ OrhqBc1j39LmNwWO1cxSn9rPITsb8tozXt3VW5hIMXPWuIw2/uVla72PNl3jS7t8 OabAgU9XWOlNQOb5Vd/4 =FyCY -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
{ANN} clojure-control 0.2.1 released.
Clojure-control is a clojure DSL for system admin and deployment with
many remote machines via ssh/rsync.It is on github:
https://github.com/killme2008/clojure-control
0.2.1 has been released,main highlights:
First,A shell command DSL by sunny87,for example:
(cd /home/login
(run ls)
(cd bin
(run ls)))
(cd /home/login
(path /home/login/bin
(env JAVA_OPTS -XMaxPermSize=128m
(run clojure
Second,Supports ssh/scp/rsync options when defining cluster,they can
be a string or a vector:
(defcluster :mycluster
:ssh-options -p 44
:scp-options -v
:rsync-options [-arz --delete]
:clients [
{ :host c.domain.com :user clogin :ssh-
options -v -p 43}
]
:user login
:addresses [a.domain.com b.domain.com])
Third, It supports executing task in parallel now,just define cluster
by
(defcluster :mycluster
:parallel true
)
At last, i recommend everyone try the lein-control plugin developed by
sunny87 for using cc much more simply,please visit
https://github.com/sunng87/lein-control
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Re: anyone interested in a small game?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 i'm not looking for people to split the work and get things done faster, i'm looking for people to think about how and why things should be done. for example, right now i have a record called gameentity which contains a position, the current health, speed, the polygon representation which should be rendered and a few more things - but haven't figured out yet where to put the logic and how to apply it so that everything is easily extensible Am 31.10.2011 15:44, schrieb Timothy Baldridge: I once wrote a test game engine that handled used a one-agent per entity approach, and the idea was that it should be close to linearly scale-able. It actually worked quite well. I think in the end I tested it with more than 10,000 entities flying in a flocking/following pattern, and the engine ran like a dream. IIRC the limit with 10,000 entities was more because my GPU on my laptop is crap, and couldn't push much more than that at a single time. With 10,000 entities on my quad-core desktop the app worked like a dream. Now all this is overkill for a small game, but it did seem to work well. Unfortunately, I'm not sure a game as small as asteroids would work well to have multiple people working on it. Simply because each part of the game (graphics, physics, gui, etc.) are all so small, that multiple developers would just step on each other's toes. Timothy On Mon, Oct 31, 2011 at 9:37 AM, Dennis Haupt d.haup...@googlemail.com wrote: one agent per entity? i'd have done an agent for the whole world and apply functions like apply-collision and apply-shot-fired to it Am 31.10.2011 14:46, schrieb Timothy Baldridge: Haha! I forgot about Java2d... Yeah, that would work just fine. No, Clojure does not support remote agents. But agents can really help in a system like this to express objects as distinct entities. That is, you have one object per item on the screen, and then each object basically can live on its own: (send entity update-time timespan) (send asteroid do-split) etc. Actually, this really isn't too long of a project, at least the asteroids part isn't. Timothy On Mon, Oct 31, 2011 at 8:00 AM, Dennis Haupt d.haup...@googlemail.com wrote: isn't openGL a bit of overkill (we can just use java2d), or do you want to add a renderer doing all sorts of awesome stuff which totally contradicts the white-polygon-on-black-background graphics? might give the game a pretty unique look :) Am 31.10.2011 12:41, schrieb Timothy Baldridge: I'd be up for something like this. I have a fair amount of clojure experience, and I've done quite allot of work with OpenGL in other languages, so this actually sounds fun! Another option to consider, is the old DOS version of SpaceWar! http://www.youtube.com/watch?v=yY5qHe2VadA I like the idea of doing a Asteroids/Spacewar! clone, mostly because it would give us a chance to introduce Agents as the building block of the game engine. Timothy On Sun, Oct 30, 2011 at 1:32 PM, Dennis Haupt d.haup...@googlemail.com wrote: hi community, i decided to create a (small) game in clojure to get a bit of non-theoretical experience. i'm pretty much a clojure noob (only did a few experiments) but have done a few real things in scala - which is totally awesome btw - so i do have some functional programming experience. if there's someone here who would like to join, just do so by answering yes or something like that. i was thinking about a game like asteroids, tower defense or that old game with lots of aliens on the top and two players at the bottom, shooting upwards. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en - -- -BEGIN PGP
Re: anyone interested in a small game?
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1
no need for IRender since everything has a java.awt.polygon. i just
draw it. in a sense, the polygon is my IRender and it's data is the
implementation.
i was thinking about using a simple type (:asteroid, :ship, :bullet)
for each entity and pick an advance-function (input = complete old
game state + one specific entity, output = new entity) depending on it.
- -
{:asteroid advance-asteroid :ship advance-ship}
i'd like to avoid mutable states as much as possible which means there
will be one atom or agent for the whole world and a bufferedimage.
other than that, i'd like to stay purely functional.
Am 31.10.2011 19:03, schrieb Timothy Baldridge:
In the OOP languages, entity systems seem to be all the rage. I
suggest stealing ideas from there if you can.
In this same vein, I'd recommend thinking about the following
approach:
First, read up on reify and protocols. Next, create protocols for
the main areas of your engine. Perhaps start with IRender and
IPhysicalEntity
(defprotocol IRender (render [this]))
(defprotocol IPhysicalEntity (update-position [this timespan]))
then for the user ship, you can do something as simple as:
(defn new-ship [x y] (let [pos (atom {:x x :y y})] (reify IRender
(render [this] (render-ship-model pos)) IPhysicalEntity
(update-position [this timespan] (swap! pos #(hash-map :x (inc (:x
%)) :y (:y %)))
there's bound to be errors in the above code, but you get the
point. The thing I love about the above example is that we've
completely abstracted away the parts of this engine. We can have
entities that implement different protocols, we can have a separate
data structure for each and every entity, depending on its needs,
and everything is abstracted nicely. Static objects can just
implement IRender, and invisible objects can implement
IPhysicalEntity. Extend this to implement ICollideable (for
collision detection), and you have the makings of a very extensible
system.
Timothy
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Re: anyone interested in a small game?
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1
this is my opinion as well:
adding a layer of abstraction at a later point in time is much more
difficult than removing one that is just delegating calls, so it often
pays off to add one in the beginning just in case. i decided to just
skip that because everything is going to be a polygon, even lines and
circles can be represented as polygons.
i did what you suggested anyway.
Am 31.10.2011 20:03, schrieb Timothy Baldridge:
As far as the mutable state goes, yes, that's probably a better
route, at least for a simple game. However I would recommend
against everything is a polygon route. Once again, for a simple
game, this may be fine, but you're now making an assumption:
everything is a polygon. What if you want a simple laser
point-to-point entity? What if you want a planet that is
represented by a circle? What if you want your ship to be a
different color than the asteroids? By implementing IRender
, you get two side effects:
1) you can now de-couple the presentation of the object, from the
code that presents it 2) you can have very complex models (multiple
polygons and colors) without having complex render code 3) you can
have entities represented by bitmaps, polygons, circles, arcs, 3d
meshes, etc.
This is what Clojure excels at...de-coupling, or as Rich put it in
his recent talk Simple made Easy: don't assume things about your
code. Don't assume that all models will always fit into the concept
of a polygon...don't assume that you'll always want to represent
your models via Java2D.
Now, I'm not saying that your idea is bad for a simple game...but
for a larger project you may run into problems with this approach.
If you want a good way to think about this, I'd recommend trying
to design the engine to run on both Clojure and ClojureScript. Have
it support Java2D, SVG and Canvas front ends...even if you don't
implement anything but the JVM version, if you can at least show
that your engine would work on these other platforms without heavy
modifications (massive kodos if you can do this without any
modifications to the core engine at all) then I would say you have
reached a higher plane of understanding in when it comes to
Clojure.
Timothy
On Mon, Oct 31, 2011 at 1:42 PM, Dennis Haupt
d.haup...@googlemail.com wrote: no need for IRender since
everything has a java.awt.polygon. i just draw it. in a sense, the
polygon is my IRender and it's data is the implementation.
i was thinking about using a simple type (:asteroid, :ship,
:bullet) for each entity and pick an advance-function (input =
complete old game state + one specific entity, output = new entity)
depending on it. - {:asteroid advance-asteroid :ship
advance-ship}
i'd like to avoid mutable states as much as possible which means
there will be one atom or agent for the whole world and a
bufferedimage. other than that, i'd like to stay purely
functional.
Am 31.10.2011 19:03, schrieb Timothy Baldridge:
In the OOP languages, entity systems seem to be all the
rage. I suggest stealing ideas from there if you can.
In this same vein, I'd recommend thinking about the
following approach:
First, read up on reify and protocols. Next, create protocols
for the main areas of your engine. Perhaps start with IRender
and IPhysicalEntity
(defprotocol IRender (render [this]))
(defprotocol IPhysicalEntity (update-position [this
timespan]))
then for the user ship, you can do something as simple as:
(defn new-ship [x y] (let [pos (atom {:x x :y y})] (reify
IRender (render [this] (render-ship-model pos))
IPhysicalEntity (update-position [this timespan] (swap! pos
#(hash-map :x (inc (:x %)) :y (:y %)))
there's bound to be errors in the above code, but you get
the point. The thing I love about the above example is that
we've completely abstracted away the parts of this engine. We
can have entities that implement different protocols, we can
have a separate data structure for each and every entity,
depending on its needs, and everything is abstracted nicely.
Static objects can just implement IRender, and invisible
objects can implement IPhysicalEntity. Extend this to
implement ICollideable (for collision detection), and you
have the makings of a very extensible system.
Timothy
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Re: anyone interested in a small game?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 if you *really* make zero assumptions, every second call has to be a protocol/interface call. *i know what i am, so no assumption* - *interface call* - *repeat* i think no assumptions should be make no assumptions about the internals of what you are calling. as long as you just code against the outer shell, you should be fine. Am 31.10.2011 20:54, schrieb Michael Gardner: On Oct 31, 2011, at 2:03 PM, Timothy Baldridge wrote: This is what Clojure excels at...de-coupling, or as Rich put it in his recent talk Simple made Easy: don't assume things about your code. Don't assume that all models will always fit into the concept of a polygon...don't assume that you'll always want to represent your models via Java2D. It's impossible to make zero assumptions about your code; the trick is figuring out which are the appropriate ones. Making too many assumptions leads to brittle and hard-to-extend code, but making too few leads to over-generalized, ponderous code that does way more than it's ever likely to be used for. In a case like this game, it should be easy to refactor away from the everything is a polygon model if and when the game outgrows it, so I'd argue against introducing the extra complexity of per-entity renderers until it's actually necessary. That's a strength of dynamic, expressive languages like Clojure, IMO: because there's so much less code, refactoring is much easier. So instead of trying to predict all future requirements and possibly ending up with over-generalized code, you can make assumptions based on current/near-term requirements and refactor when those assumptions no longer apply. - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOrwmYAAoJENRtux+h35aGTQgQAMC1bUbjN0Mz90fmOQVUCjBN zO+UJXfaiVo6DmR0usZkv1ynwTyuZwQm+llhamabAMLUZXsIiAcbpu0KLjkxJwjJ S6EpZwAsRnqYtUTn3DvdFC3kTkgUR5+KD7fQ97PBHBmyNKcy+GcU7MQP0bsZ9KdQ 26K6qo5TqWmkQEzvg9kVBrB2W5FQj6BuH7UA3LQxHSegpc4Wryxf9qQZFEa5mqFg IdRUFFR2oLOD1rCBcVoeV9hvyPeIdw8ntHoVVepfeDN+PspC3Z58f09dr9E8gar6 Jp9DSgOsZr6ClUHVGUhVOaWPiFeZLunOe9cOCJTaanXKzkE1fejzuQez51sAo3ns mSF40Ezip30kTpJWld1mQV4/mFgsmfymegQiJ71r8V0nEJxOESpmGPb3by0CIAyE sqoFyh/oqbp8lwupwHI636L6O9DPqKYwIVv1ba0q09NhO6rbvDe93+9lWTs3n+XB XLJprZjoU8A7PtUxCEdVCWx75Hi5Lt3FXaFeF/36clWCftRC9yyy+61ZAM5UrmsC 4QjUIG3jJCX7aeHteerWZrkApieYr5JBxL81Zyvf6at0wnINr/x8drWuB8R9gwKy gBIpi+WrjSZhlCgkaQnJocgxrMhNTkdk1XsRcdHDFt1j5kLfb3ZdjK+rSr13XX0H 5FLhhzQZOnnlDibXw1P9 =nWrK -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Can't take value of a macro aka macro noob needs help
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 i played around a bit (defmacro times [times exprs] '(let [countdown# ~times] (loop [remaining# countdown#] (when ( 0 remaining#) ~@exprs (recur (dec remaining#)) (defmacro forloop [[i end] code] `(let [finish# ~end] (loop [~i 0] (when ( ~i finish#) ~@code (recur (inc ~i)) the second one works fine: (forloop [a 4] (println a) but when i try to do the loop without an externally applied counter variable, i get a runtimeerror: Can't take value of a macro what exactly does it mean? it also happend when using expandmacro, so i guess my error is really, really obvious. but what is it? -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOrV29AAoJENRtux+h35aGEfAP/AjDZ7VpZOB7xg6xuhWfe0UO pKH4WG5CDWF4MdezuWvS1n3D6V60cLV2DwdIS5K8TYBHnYKe6iKQwdpssNpDe4HE 3MwmYQIF8X4rbezH5XXhyR1WnWBAKJLrkTg1oB6SJNvUlotF8SnhjYTmROXX9sfV OE+AiR0Mt8QoxKGnCBQOSDhAw0IMVdKpuAqTbfggUVJD1mQTY+fHA3kwFfh+k2UR XWcYxRTFIEcK3guVzKBYk0FyBT9A6xBu88En7yzgBUC9fqwwmzN/Q4msIXVq2Ep4 /7p28YQnLEa+PJmQJlLN5bwEBbrsyMAvyvmVU4JbUznIc+o2mCx2Lny9Bv64NAYS aesIxwp9Qn4enkYtvqdSfyTonEZRyA+O5gmcjPgpZfIuHYiVPgP2Kibr36T9TU5L CjnKblyRvHyM0a0jo2hfh3D7HNPBzp11aWuB5/wJ3pxqL9yjzdmSKfTW8SWoKgYL yObnt3e/d4Zm+yZ2+J/THP4AtTZfo4M365Swo/rypDjuecwvOXyTiGA+nbZUXF/k j8ptkAvOQQX3GZ1btzWE4Wh9+Q0eO6wO9IopNwvwnffC9k7OZ0AebYfynzsBwv/V LTtNKC+HGrcpvw1gxpF4rnkmjjPWHtn413GwKLNaGMBVmTZ05gofIuR2sQijBRfy 6JF2sFkMro16WxcGf0rw =estl -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Can't take value of a macro aka macro noob needs help
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 your magic eye is right. using a backquote fixed it Am 30.10.2011 15:37, schrieb David Powell: On Sun, Oct 30, 2011 at 2:22 PM, Dennis Haupt d.haup...@googlemail.com mailto:d.haup...@googlemail.com wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 i played around a bit (defmacro times [times exprs] '(let [countdown# ~times] (loop [remaining# countdown#] (when ( 0 remaining#) ~@exprs (recur (dec remaining#)) It looks like you have an apostrophe in '(let - it should be a backquote. Also the error message is confusing because you have named the parameter times and the macro times with the same name. -- Dave -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOrWkcAAoJENRtux+h35aGhXsQAKlTzH85uqEBSGQsGHwBRYZK nn7xxj/eWbP/nmIhPiHZhBXAkgPfItQZl3SHwjwiKgs5xS8MJVFXZKhRW/2AX6RQ jIxe2ORK+CmfZamDzeaRnf1dql32aV1qOxb2hXC/VvaAxP1bLOw1X4iykXB8kqFE AUEMMGnilpWiihYqGGFYxlE3TzvVYUK2SCmah9CESYjW7PyR9QyiAZYvDxfGqC/G As+JbDloapSt2FiTsNzjXZ14/qlGRhlfP3p3bdZmLlpDpzFrbPnka95QCXS7yG3P hIvRVTUGkOec3jRWWEAXWnzEURu1LF26KB1QMuJHV+EB7tS+mqGXuwaW5mSiyi/b U2zKdV5QePvkjk0BkXSDtKnZXP2Mydn/G7PNAwLMdMJVj+yVqV/UlbcU/68lBVRs g/SDcaSaGzFao+V5iwXLVj4NuTTW4iAvy50nIORtc+A8ikoNhk2+X6+SVkgTo15L /MNzDF0goC9KpKEt1hJtmJblnyaKqGmXMK45i4QBBiCoHpgYTHdDITfIFqQHBKew YzBiNkkcS2WkEkkDeQcnsrdMiEw23LjYTz/G4p2j/+VLuKsfDp9Qegat2iVKWAup EN2Q+302NviZSAGw12en/09k/5PNT5QeBCexHlCI6xkeu5cxJMOQwkgQDzrrZgAP ZabbzWcl931nYi+XvKxP =JGAi -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
anyone interested in a small game?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 hi community, i decided to create a (small) game in clojure to get a bit of non-theoretical experience. i'm pretty much a clojure noob (only did a few experiments) but have done a few real things in scala - which is totally awesome btw - so i do have some functional programming experience. if there's someone here who would like to join, just do so by answering yes or something like that. i was thinking about a game like asteroids, tower defense or that old game with lots of aliens on the top and two players at the bottom, shooting upwards. -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOrZhRAAoJENRtux+h35aGzE4P/2llb/0Pfy/qJSjK0pEM/plD ySU/CYupObaI3aZN+1aK8LwCQmiznyk6AUa8UcdO9fYcvEXDTBvHbWJUpimG0gUC pMUuL/wfTqB232gtuNbYMc6zYRoN3ddq4yZIq0QFnbqXI8PaxjQJBaS7J+5DZEGG JXaaA9RpTL6mnyTxxlw29BwHgmsv+xxbu09yAg8VHABD2TcuRUuz81OKmHTUxxhm 1ZtlP9dw+jVzryNUHfE3lygn+stfIJxC3ui3cf4Rfham+CbhjpseClkXWA4nNYYF tqsQHxxe76CewXbQBpnKhqPvB9REo+qGdADi6camML5k+i6FYen4QXIvh5bF8PmO jkOFQZLN2t05pPEmq+lamMmpb3LA2VLVv4zC/m9mEgrJ/rB34Ewv1upU76Qme+OB r/++jgFeb0OcjdFs4kvJpF7wKFKHJv0nMfyzKnzrx4D0HckrpQdsBGsXjhDqsvZQ 6QwamOZhk9yugPlqgEy3eN6VrKxY9JawQ0H6e5P+DD0F7UyDbYtBk/HcEx916Kjj CBNEIwImHoR/0uA7Dyzrn08LoaTcej7kSA06UOkOiRaw71T9EnQuOjDDabrzmsyk Go/R+rPMlgFTpdt6w43dnmmXqrOfKJqmFrvYztKBAulVoibY0ZSkwmKd/cftiYNw WSOA0yQMG5qN1pBmpiCk =j+7J -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
A memcached client for clojure wrapping xmemcached
Hi,all I wrote a memcached client for clojure wrapping xmemcached.Xmemcached is an opensource high performance memcached client for java. It's name is clj-xmemcached,and it is on github https://github.com/killme2008/clj-xmemcached A basic example: (ns demo (:use [clj-xmemcached.core])) (def client (xmemcached localhost:12000)) (xset client key value) (prn (xget client key)) (xcas client key #(str % update)) (xshutdown client) More detail please visit the github homepage. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: A memcached client for clojure wrapping xmemcached
An example with more detail is on https://github.com/killme2008/clj-xmemcached/blob/master/example/demo.clj 2011/10/29 dennis killme2...@gmail.com Hi,all I wrote a memcached client for clojure wrapping xmemcached.Xmemcached is an opensource high performance memcached client for java. It's name is clj-xmemcached,and it is on github https://github.com/killme2008/clj-xmemcached A basic example: (ns demo (:use [clj-xmemcached.core])) (def client (xmemcached localhost:12000)) (xset client key value) (prn (xget client key)) (xcas client key #(str % update)) (xshutdown client) More detail please visit the github homepage. -- 庄晓丹 Email:killme2...@gmail.com 伯岩(花名) bo...@taobao.com Site: http://fnil.net 淘宝（中国）软件有限公司 / 产品技术部 / Java中间件 -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Can Simple be done with Static Typing?
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1
i have some (10 years) experience with difference statically typed
languages and a bit with dynamic ones. i encountered a few typesafe
solutions that don't introduce a lot of overhead - for example the
types of scala. in addition to interfaces and classes, scala has
types. a type can be an arbitrary set of field and method definitions,
for example:
type foo = {
def x:String
val y:Int
}
every instance that has a method x which returns a string and a field
which is an int are compatible to foo. in java, you would say it is a
delayed interface. the code behaves as if someone magically attached
implements foo to any class which would still compile.
so your (not (nil? (:first-name record))) would work in scala if
there was a type like type bar = {
val firstName:String
}
it's implemented via reflection, but the types are checked at compile
time.
Am 24.10.2011 15:28, schrieb Timothy Baldridge:
After watching Rich's talk the other day about Making Simple
Easy, I started thinking about how to incorporate parts of this
talk into the software we're writing at work. During this thought
process, I have begun to wonder, are simple and statically typed
languages mutually exclusive?
Let me explain by a simple example. In the following text, I will
be using C# as my example static language, and Clojure as my
example dynamic language.
For instance, let's say we have two structures, Contact and Staff.
The two are completely unrelated, except for the fact that they
both have a first name, and they both are required fields:
Clojure:
{:first-name Billy :age 42 :record-type Contact} {:first-name
Joe :position manager :record-type Staff}
Now in Clojure, writing a validation check for this is as simple
as:
(not (nil? (:first-name record)))
But how would we do this in C#?
new Person() {firstName=Billy, age=42 }; new Contact() {firstName
Joe, Position=manager};
Person and Contact are unrelated, so I'm left with duplicating my
validation routines (once for each object), or going and making
both implement IFirstName. This gets even more fun when you start
taking into account generics: In C# a ListIFirstName cannot be
casted to a ListPerson because they are considered two completely
different objects.
In the Clojure source code, Rich gets around most of the above
issues by simply referring to everything as a object and then
casting to get the type at runtime. This works fine for code that
will be run in a dynamic language anyways, but makes for some ugly
code when you're actually writing the static language parts:
if (lst[0] is IFirstName) runFirstNameChecks(lst[0]); if (lst[0] is
Person) runPersonChecks(lst[0]);
However, this then requires tons of type checks and casting
throughout the entire system.
So yes, I understand that this is all a bit off-topic for a
Clojure mailing list, but I thought it was applicable to Rich's
talk. Are we getting half way to simple, simply by using Clojure in
the first place? Is it possible to write simple code in a language
that shuns the use of simple containers (List, Dictionary, etc.) as
the primary transport system for data?
If anyone has some thoughts, they are more than welcome to ponder
them out-loud with me on this thread
Timothy
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clojure newbie collection question
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 if i got it right, filter/remove and map (basically all batch transform functions) return lazy sequences. to convert them to real collections again, i do (vec lazyseq) in case i want the result to be stored in a vector. correct? what happens if i traverse the lazy sequence more than once? is the result cached like in a scala stream, or is a lazy seq in clojure similar to a view in scala that is calculated each time it's traversed? -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOmHZiAAoJENRtux+h35aGHYIQAKeYGf6BEsBVvlTbxF0NEiM2 O9u8jPnUwpRcqsoslROX8YCKpTjppnG/YpaGI98OkZXPLXK6f3JDo60gV6oF143L mntpi1RrQ3DDPFfFzsSGpK1k/eoqaR+E6dOeWOeC/FkGjotjaDN4KlJp9PsdaAmZ 2atZX2Nr8Ock+gRnteupJEbWPJ5kbPm0W/cYojnCGKgPcxTZ67BFEnpTtWfYzPGC v5vn8+OP/dw5kwAgnvQoSl4AVB7BkGFL4dDeKeayR6MstLKlfl8mJeecliZlc4iy rbMWIu5rHJGYyFDnejzbubfwSkYUrCtfMjvD4Zz69ArTLOrWtKKe+WDFFawi0QeM gYleGeFPhX9adHF/uyojDljy+LhnX65+2Q5fnUXTa5+QX0F3oxrCs9C0lPJwmYpy HplJrh7YoeHRXSh/vlBm5Y8FMaIwW2mCn7SmdldHZz0TrURwQaD8hUwgNl6fMPgO YOe2lopReZofT7jdR40fhtGakv/+RFwhgDZY66zp13b5ab79uhMrt0jMG3pHHwgs 2bBeZol2V+RsROXi2aVOBPrRQWpVDWxQn4Ky/0PV5QjapqTNe/2ZDxtCM7O4acqf 9f7XoY1tWYhWNCCkHtl9VvkqQJtgeJdkODd4+ksu1hhg70JfE++q4Drml31wOpNo 3vCvGa1fsATKhsbzc9zi =sU9o -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Shameless self promotion - JavaOne
Here is a link to my presentation. http://dl.dropbox.com/u/5831287/JavaOne%202011%20-%20Monitoring%20a%20Large-Scale%20Infrastructure%20with%20Clojure%20FINAL.pptx Sorry about the file format :) Let me know if the link doesn't work. -- Dennis On Tue, Oct 4, 2011 at 10:17 AM, C. Arel java10c...@gmail.com wrote: Hi Dennis and Chas, I'd also like the slides if possible. Maybe if you could post them here in the group more people can get them. Thanks, Can On 27 Sep, 17:50, Dennis shr3ks...@gmail.com wrote: Hey guys, I will be giving a talk at JavaOne (it is Clojure related). Here is the information. Title: Monitoring a Large-Scale Infrastructure with Clojure Time Tuesday, 07:30 PM, Parc 55 - Embarcadero Length 45 Minutes Abstract: Monitoring a large infrastructure brings unique challenges that require blending development and operations concepts. This session discusses how Dell Inc. used Clojure to develop a data-flow-based monitoring system that stores, evaluates, and acts on hundreds of thousands of metrics. It covers • Real-world applications of Clojure's parallel programming constructs to take advantage of multiple cores available in today's systems • Using Clojure's homoiconic nature to create DSLs • Taking advantage of Clojure running on the JVM to use the Java ecosystem • How DevOps takes advantage of the JVM dynamic languages to develop new monitoring tools Track Emerging Languages, Tools, and Techniques Optional Track The Java Frontier -- Dennis -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Shameless self promotion - JavaOne
Good idea. I am having problems with slideshare displaying the presentation. I probably need to get on another machine to try to convert it to something more useful, and that will take a couple of days. I will post when I do. -- Dennis On Wed, Oct 5, 2011 at 12:05 AM, Leonardo Borges leonardoborges...@gmail.com wrote: How about putting it up on slideshare? Pretty sure they can import pptx ;) Cheers, Leonardo Borges www.leonardoborges.com On Wed, Oct 5, 2011 at 3:55 PM, Dennis shr3ks...@gmail.com wrote: Here is a link to my presentation. http://dl.dropbox.com/u/5831287/JavaOne%202011%20-%20Monitoring%20a%20Large-Scale%20Infrastructure%20with%20Clojure%20FINAL.pptx Sorry about the file format :) Let me know if the link doesn't work. -- Dennis On Tue, Oct 4, 2011 at 10:17 AM, C. Arel java10c...@gmail.com wrote: Hi Dennis and Chas, I'd also like the slides if possible. Maybe if you could post them here in the group more people can get them. Thanks, Can On 27 Sep, 17:50, Dennis shr3ks...@gmail.com wrote: Hey guys, I will be giving a talk at JavaOne (it is Clojure related). Here is the information. Title: Monitoring a Large-Scale Infrastructure with Clojure Time Tuesday, 07:30 PM, Parc 55 - Embarcadero Length 45 Minutes Abstract: Monitoring a large infrastructure brings unique challenges that require blending development and operations concepts. This session discusses how Dell Inc. used Clojure to develop a data-flow-based monitoring system that stores, evaluates, and acts on hundreds of thousands of metrics. It covers • Real-world applications of Clojure's parallel programming constructs to take advantage of multiple cores available in today's systems • Using Clojure's homoiconic nature to create DSLs • Taking advantage of Clojure running on the JVM to use the Java ecosystem • How DevOps takes advantage of the JVM dynamic languages to develop new monitoring tools Track Emerging Languages, Tools, and Techniques Optional Track The Java Frontier -- Dennis -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Using Clojure to Generate Java Source?
Thanks for the advice and support everyone! I'm not hopeful at being able to sway him to a parenthetical language through logic (I've tried!) Additionally, I definitely would not consider throwing out unmaintainable decompiled Java code on the sly. That, as Nicolas pointed out, would be the ticket to finding a new place of employment. :) I'll try and make the case with him and our mutual boss for letting me work with interop until we get some time to re-develop a pure-Java solution. I don't expect the pace of development to slow down and perhaps proximity to elegance will make an impression. I have to respect that it's his project, but I definitely cringing at re-developing this thing imperatively. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: producing Blub code and vv.
Nice article in the wiki link, the logic rings pretty true for me. Clojure is a truly powerful language and I don't want for any higher-level facilities with it yet. :) That said, it would probably mean great strides in the industry if elegant Clojure code could be translated to comprehensible Java code (or to other languages.) I feel companies use different tools all the time as long as it results in efficient generation of their lingua franca (Java, Python, Ruby, etc.) They switch languages very rarely because it takes a revolution in philosophy to unseat a considerable investment in a particular language. If Clojure could translate itself into other languages the adoption argument would be reduced to getting someone to let you use anther tool to auto-generate boilerplate (the same way IDEs might generate Java getter/setters.) Only this tool would come with lots of parenthesis and a REPL, among other things. ClojureScript being a prime example of Clojure 'speaking' another language. This type of feature is probably only useful as a bridge between now and when everyone in the future talks in reverse polish notation. However, I think comfortable proximity to Clojure's elegance and efficiency would help other developers slowly become acclimated to, and even secretly curious about a new way of thinking. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Using Clojure to Generate Java Source?
I'm in a bit of a bind-- I've written some really nice Clojure code for dealing with Genomic sequences that works as well or better than the reference implementation we currently use where I work. However, the the hierarchy has recently changed and my new boss is requiring me to have all code in Java (eg. interop is not an option since he wants the source to be pure Java.) Is there any way to prevent my head exploding from hand-translating my Clojure code into Java? I'm sure it's possible to generate Java source since we heard Rich's amusing anecdote about using Clojure to write reams of Java boilerplate instead of doing himself. Is there a precedent or even an existing library for translation from Clojure into Java source though? I'd like to be able to use the code I've got without a long, painful devolution. More importantly, I want to be able to continue developing in Clojure and just compile it to Java source and check that in. Thanks, Dennis -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Using Clojure to Generate Java Source?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 compile to java class, decompile to java source. works in theory, until someone actually looks at the source ;) btw, your new boss is ... not the type of boss that would keep me from looking for a new job. Am 29.09.2011 20:09, schrieb Dennis Crenshaw: I'm in a bit of a bind-- I've written some really nice Clojure code for dealing with Genomic sequences that works as well or better than the reference implementation we currently use where I work. However, the the hierarchy has recently changed and my new boss is requiring me to have all code in Java (eg. interop is not an option since he wants the source to be pure Java.) Is there any way to prevent my head exploding from hand-translating my Clojure code into Java? I'm sure it's possible to generate Java source since we heard Rich's amusing anecdote about using Clojure to write reams of Java boilerplate instead of doing himself. Is there a precedent or even an existing library for translation from Clojure into Java source though? I'd like to be able to use the code I've got without a long, painful devolution. More importantly, I want to be able to continue developing in Clojure and just compile it to Java source and check that in. Thanks, Dennis -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOhLd6AAoJENRtux+h35aGCe4QANMbLKUwasgC5Ue5O+Ad5ozt Pl0zWDbS29iPYP7NtafPltBUxypZrkDWlT/8mbZW5bkCe2R5V/JyzVO34eIZsUCs AhcC7TlIXTl8UQQJVC+zKwZ/S6URHApEKI097rxJVGqKEDqjXS7tytqKXYM4hrOp H1Iu8SQyGdDgEOjL8VQHTGiPeovM6lzW1evK/iqvlUlgDmD5B11ectI9tSrITPn9 IAl+7RK7FcM7B5PESY+GKG4zbitEy4M1UKNQUq1XaCwx2qWERQMhvNrujjUCO9jX m+na6X5u7Cl/xBxxl52n053e/zQjJK4rdLAgm6K1x1b/t7kofrf+3D9BLCYdr9GY /1mYhOm1THXgNCYfZYMbDzEwKSy3molnCbPr7pryqj9IJjJ5fEPAfXmSZa7ESZSm MeEPKnDEhfKSV+NvuQ9srZL0XrN/YDJ+IIckAc1hoAGKUmH4bf+kkhWkD2+cgft2 PO3DG+5kaXy0rc3lP1XAntTQQufIfTwOu69DFPVhOTKHRaWCn/SxDlW2/D3CytU5 MFc59ZKON6sz3L04/9ihnMonW1E/VYl2dvEL/v67s+hkDfc/la4fNpyDP0jnOa6b didf/CLOoXDf96gkLe87R9WPdfdMgjrWvq+oz+T1JmUN7mCuwb0ha13JrnxBqLIJ bBwNY9PsIP0B9nJWZCgs =C3mv -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Shameless self promotion - JavaOne
I am not sure to what extent there will be recording. However, I can send you my slides after the presentation. -- Dennis On Wed, Sep 28, 2011 at 12:47 AM, Boris Mühmer boris.mueh...@googlemail.com wrote: Will there be any slides or maybe even a recording of this session? I would be very interested in this talk, but I can't go there... Regards, Boris 2011/9/27 Dennis shr3ks...@gmail.com: Hey guys, I will be giving a talk at JavaOne (it is Clojure related). Here is the information. Title: Monitoring a Large-Scale Infrastructure with Clojure Time Tuesday, 07:30 PM, Parc 55 - Embarcadero Length 45 Minutes Abstract: Monitoring a large infrastructure brings unique challenges that require blending development and operations concepts. This session discusses how Dell Inc. used Clojure to develop a data-flow-based monitoring system that stores, evaluates, and acts on hundreds of thousands of metrics. It covers • Real-world applications of Clojure's parallel programming constructs to take advantage of multiple cores available in today's systems • Using Clojure's homoiconic nature to create DSLs • Taking advantage of Clojure running on the JVM to use the Java ecosystem • How DevOps takes advantage of the JVM dynamic languages to develop new monitoring tools Track Emerging Languages, Tools, and Techniques Optional Track The Java Frontier -- Dennis -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Shameless self promotion - JavaOne
Hey guys, I will be giving a talk at JavaOne (it is Clojure related). Here is the information. Title: Monitoring a Large-Scale Infrastructure with Clojure Time Tuesday, 07:30 PM, Parc 55 - Embarcadero Length 45 Minutes Abstract: Monitoring a large infrastructure brings unique challenges that require blending development and operations concepts. This session discusses how Dell Inc. used Clojure to develop a data-flow-based monitoring system that stores, evaluates, and acts on hundreds of thousands of metrics. It covers • Real-world applications of Clojure's parallel programming constructs to take advantage of multiple cores available in today's systems • Using Clojure's homoiconic nature to create DSLs • Taking advantage of Clojure running on the JVM to use the Java ecosystem • How DevOps takes advantage of the JVM dynamic languages to develop new monitoring tools Track Emerging Languages, Tools, and Techniques Optional Track The Java Frontier -- Dennis -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: can't see the error
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Am 27.09.2011 06:27, schrieb Baishampayan Ghose: i wasn't really trying to achieve anything useful - just messing around and see where i get. now i'm here: (defrecord point [x y z]) (defn genPoints [n] (let [random (new Random) randomInt #(.nextInt random) randomPoint #(new point (randomInt) (randomInt) (randomInt))] (repeatedly n randomPoint))) is there a way to avoid writing (randomInt)(randomInt)(randomInt) and instead something like (magic (repeatedly 3 randomInt))? This is how I would write it - (defrecord Point [x y z]) ;;; Only needed in pre Clojure 1.3.0 ;;; In Clojure 1.3.0, -Point will be generated automatically ;; (defn -Point ;; [x y z] ;; (Point. x y z)) (defn gen-points [n] (let [random (java.util.Random.) random-int #(.nextInt random) random-point #(apply -Point (repeatedly 3 random-int))] (repeatedly n random-point))) Hope this helps. Regards, BG yes it does :) - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOght3AAoJENRtux+h35aG+AIP/j3ufGpS74wSSDv1RyAJjx2V S7cdRuF4U00tanW1OAn/PYY93iT0wcXBgKowuo/jD9+C0TV5K7/he33KeSRrJCnb vLEq8B1Um4JOc1V7MZZBaqtIfJcaQ3s5fcPtPdITX97dX79A3WSItU3/Fc+UYC2i eF7p99dNLToF2KQhQPZ0Wb37gyIit/XExWiuTx8FIkNzLsL/cPQFMJpcG5Thw9pF 6EKImZOH2A6zOgO68nbynxV4D2vOW7VKkJb7B61XgRILf9bfLqspg/GmEeXaBTrp gNXSbE7AFAHp6bA08nvydfr9H68z1H53i79mLxlDVXsq3MjGiHVddDa1SaG9SwwV Vt7K0IndKqFonoI5WUj9CRnxWDoDhy35zwSolJOZhAjSSBHDdZCa9fa0BUU5HXu6 15z3RTG9nOk6OIQJeJiKNGaHtPdplJ0ugHFCDhLpsQZoG8z6QWT6n6BxDwRU9w3i bEobBms8PqEsTWf1MmwJxLPyA/UC0wVKNiMdqheyydVZ/siGJzXN6fgJYFFUXPhT KElmSJPeV6Ee56GG2ttDFSSblP+At2Kv3zJZQqUnbEhiu6a3L6ofrybTkaUjASWK KXcnTYEy/ARi2lc+lD39pgM9YKJOOvgX9f3cGFe8mi4B1nZ5nlzrciyN3eJy8QaL /MJvl1yQRxdWqQX1xLsQ =vR6l -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: can't see the error
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 i don't have the magic eye to spot the parenthesis-errors yet Am 25.09.2011 22:15, schrieb Mark Rathwell: (let [rand (new java.util.Random) nextInt (fn [a] (.nextInt rand))] ((map (print) (iterate ((nextInt dummy) 0) extra parenthesis in three places, and the first argument to iterate is a function, not a long: (let [rand (new java.util.Random) nextInt (fn [a] (.nextInt rand))] (map print (iterate nextInt 0))) On Sun, Sep 25, 2011 at 3:51 PM, Dennis Haupt d.haup...@googlemail.com wrote: (let [rand (new java.util.Random) nextInt (fn [a] (.nextInt rand))] ((map (print) (iterate ((nextInt dummy) 0) the error is: java.lang.ClassCastException: java.lang.Integer cannot be cast to clojure.lang.IFn (NO_SOURCE_FILE:0) why does it want to cast my 0 to a function? and how can i get rid of the dummy parameter [a]? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOgLayAAoJENRtux+h35aG5UgQAJMV850ntNNio3g2HCcaVj4E LH4KfnIhC0otFrEQQfHg3ha+mBuo9flt55NnHGMfEBNdxCTkfpm0SDzqt6QTKBRA aGDDJuTyAbmnSvGnOkk60RRqeVS1QOErRyjzrMugNxguNQ5ZUKmZ5GeTndLHn0w0 g81CRfF0CSLD8j9ng98iJOdn/VwyijeATQo2b/DQhkyKHyFzlyGT3LXrRgWYAI5o NbCzMC1K/0o9LPyP9TGBvOoRrKQ28WzMsJGWhV0bWNmsMzeZokE99UDSUvYpRM+f OpyL/4MCkW6f1imGWzLpSBMHZqLSwkXX7U2fNrMGj1zi4knir/D3LF+aw5XLmkms oS6IO5qnttQ1IHCsdC9nflYfk891CNEwgGS9jG7RPJ75Zls6VzYL6zT8V/RN1xr3 3s2fYVH2elIM1SVXphTRsY5bqw7xNa0Jti8ual9j5+t+HiQ8qyqX6Yxf6KQZ+9Ux EkfpjjFw2Fh4JpJ9dYK1sOncho9j18TLE6afUuTLPYqPlhV5b0AcpPJ3XEA0ayef U2Plapgp4Jxk6IMGAoMyD/fyaRkiOKIQw+TucWc4F2icX10LjVbM2eacyKLwvwPo gmgGHfNyRj4dHOmRv40x9JheRiqJdXtuoWEks9wSY3D6sUS3qWNplCwfpJMWhIhT Dc/HVQYRIunjZ+cGALHQ =It6H -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: can't see the error
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 i wasn't really trying to achieve anything useful - just messing around and see where i get. now i'm here: (defrecord point [x y z]) (defn genPoints [n] (let [random (new Random) randomInt #(.nextInt random) randomPoint #(new point (randomInt) (randomInt) (randomInt))] (repeatedly n randomPoint))) is there a way to avoid writing (randomInt)(randomInt)(randomInt) and instead something like (magic (repeatedly 3 randomInt))? Am 25.09.2011 22:14, schrieb Baishampayan Ghose: On Mon, Sep 26, 2011 at 1:21 AM, Dennis Haupt d.haup...@googlemail.com wrote: (let [rand (new java.util.Random) nextInt (fn [a] (.nextInt rand))] ((map (print) (iterate ((nextInt dummy) 0) the error is: java.lang.ClassCastException: java.lang.Integer cannot be cast to clojure.lang.IFn (NO_SOURCE_FILE:0) why does it want to cast my 0 to a function? and how can i get rid of the dummy parameter [a]? You have too many parentheses in your code. The error is coming because of the ``((nextInt dummy) 0)'' line where you are trying to call an integer (the result of calling nextInt on dummy) as a function. I don't know what exactly you are trying to achieve here, but assuming that you want n consecutive pseudo-random integers, I would write it like this - (let [rnd (java.util.Random.) next-int #(.nextInt rnd)] (repeatedly 10 next-int)) ; substitute 10 with desired number Regards, BG - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOgO+8AAoJENRtux+h35aGF2kP/3MGVpxqqkax5O0kmX/Kh9u5 b48b6YrlgPwbSvTra2aqs+4rLF4U8mUUN82XyacB+PFAc6PeE3I8/aJudUvFO0RP c8qL31NKPSm8RTvhPWzBejh2pyu1cP4qZtmgrSFfSan34n/oadfi0w8c1AjHsQqr MVMMo2gY/U4J68wG2I7bNdbx3VT1OtmZlY04UBh5D9F6NXJ11+hEZLS89K32F6up hi0EoruOxgeJnWDMLdTsKCUiSzlI8m6ZSlRVu8aj/xkdfcDXQhNVLp/UEmKhX355 wdkZm7VHHKop1c057vlXO8Fz6eUZ2E1RV3jf2osieg3Exj5s4cHncUES5cxZ14NF 6b0Avqxf69yX5ids2OOTaTqWrniRVqhf2KyDZGmgJfgwDyfLxMeephp/3glfYrbf L3CIsXmjwebtFkwDm9LJvO8DXsOY+NU2ZgwfGCRqbwNxQU+0TMsGGgIypvD2rnM1 zAQE9kmcKLALLOwFcu6hN/OntpjtOk5e51hA7V/1oAk8H0BWOEKW1aYMggwoySgG ti9BPg8MqyTBtZmqFUyOPFH3EQr8sEjRXpu2Wf1RxATShfNWwalqeOHbEhV/vJkO SunWpUn/eqKaTzAq+ZI9VrWteMrmklHDlo7PhEwkp6JVFxUj3psfkQeqdY9fSRjz Ei2jqCQXBMRO2CGEC/+R =bKcz -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: beginner question
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Am 25.09.2011 14:00, schrieb Stuart Halloway: the website says: deftype supports mutable fields, defrecord does not so deftype seems to be what would be a java bean with simple properties in java Nope. :-) Domain information should use defrecord, and should never be mutable. This is the closest thing to a Java bean, but is radically different in being (1) immutable, (2) persistent, and (3) accessible generically as a map. Game state would modeled with defrecord. what's the difference between persistent and immutable? deftype is for things like custom data structures. In a Clojure-in-Clojure implementation, deftype would be used to implement maps, vectors, and lists. deftype's mutation ability would be used to implement transients. Stu - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOfyimAAoJENRtux+h35aGtacQALmFsfHsPuCMt/QZM1gfwMNN e3C0Q2Dju0GgG/PNGTyV25mWII0JGrvl5UK13VLb2q93bNW4l43SeS4glxE1USBd Btbo1QwGiAkIffhSrcXLQT+2K4PM4b0fbLwkF41obAEVEf3JDpMjZ9Qjxbrz9D7v WDH+JBx5rQxvk3ctPqtK59OCkH7fRtMM6bLuwHdFc9YhQt7VjmloaZaAmuXfL3+B sq//dTOuUy94ZZSsERUWWYeqRIvL5gTVkT1QTbElVHCzixH25fnTX8G3b/04bmX6 ME2P/3iSsrYdHfO35caRwQfIm29JYkljwER1vyX0n4iotouodOyTxo4s4du5PZM1 G+xWrzw65ejn3Y6GaSOFjb02wJUhku2cHyXcjY+Xdb3RXNgtTBQurW5Jx+wCmGV5 Kj3GtharuM16n4weCS0aK5meNFFmu8Djn11+cWePyjQ9qVos1ei3f8s01bN13Qbv p1qUh+5D4eJb39A4cETrJpINXIhXf2Ngg7tpyQQjzppT/iqtIVdKHMVFOiazHzh2 1aLFCBRGVoErCukB84fCmwZ9JJP8NiRzyw7choMbNeBREKhX9+WFJfwDZyygrezD kTRa7F2iwz1gEfO3kP8vevdObmtQdQgAMxQ/4IG4xLtmptfL25U/5pgvvi9jOX5T WYY70N5yr64Evgw6Bt9S =y3Ge -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: beginner question
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 so there is no difference. Am 25.09.2011 15:28, schrieb Stuart Halloway: what's the difference between persistent and immutable? See http://en.wikipedia.org/wiki/Persistent_data_structure, which now has a nice shout out to Clojure. Stu - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOf3QyAAoJENRtux+h35aGsKQP/jHBNqhUCQfSQ7XjCe3vTlF5 zhjcXmyhWbRUF7fEsrmljtpOu630gAnl51cmlBOwpOQXLmGJg386422GzUtRexG3 A4KcrYEahAKBK5R1Tiu3WMqAr/h3t9oYi6APYaU29qJqqO6lnZR/bp1yAR+wnmZT ausVGzUlE+p5DlfWHAMaAsEVYp1XX282BKecgr/cHsBy9Jwl2NdWQl0Ss/ZYPj7x JE04/y6T/1jomWdM+dwXZ/oCucWmDjSgg3nHMUy/P9yab0kN2qHprqomBCBQeOpj zY5KS2/0x6nS9XpNfKF1f7VdqG8RkVdE+iE14a5uzCWzAQfMbeZUQcyOv8H8QQXU v0VYO1htvWwoJRqoCUan5UhrucM+LDqFEml7n8S4y7kbWWy9CJHD0bq9VjgIBIJY oo8VrFM7ciO+9mmJ7VfdNmUKPmcclWVFp3PVbNKJVMFXO7s+Myj5y/irWDJ3fBTY VYiCKNtbU9uaNZRVfyTQhVF5i+607BfH78S6wA1fEXYWWcvNiwEBoTaKi4cHh6wF nbaVf2xOLahJngEg6m8yBQfcnRm5H6WZ2h53UA+c1AgwiRgOAt+FGiK6J695EZbp LlslJGUH9QVZXsDVWPthtr2Qk8fJtT7c7UQksfYU+F8lANtyTMcN/kAQ2ngZ2pbq aLOthkidIm51E9NkBRH5 =SNNL -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: beginner question
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 so persistent is immutable + x like car is movable + x. it doesn't make sense to ask what the difference is. Am 25.09.2011 18:59, schrieb Phil Hagelberg: On Sep 25, 2011 6:12 AM, Dennis Haupt d.haup...@googlemail.com mailto:d.haup...@googlemail.com wrote: what's the difference between persistent and immutable? I have written a summary of this distinction on my blog: http://technomancy.us/132 Hope that helps. -Phil -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOf3/bAAoJENRtux+h35aGFrIQAJCTY0ZVAQ1LHda9tIkiV/am hi/bSleO4qFJceGUWuoDP8nrTIc6kDZrhNv7IIYeV59GzETYsEctfUIIosNEnS94 Oya6DpoOWLFlVwLsSVrIkFNbl5WEnEhoi7myO3zxuO0PksefmzLs57oC5ijw24PP 3CQrGiLpO1dI9s7bk8fBEuBDnC+d0GOZH4YAa3EYMp/1VQoRFLgBy3Occ1DVcqcZ nTac2Gexru0vA9On1RW6d0xSNEPQk33gAnt5fU72LCTi9bAekEPb66y538LKElS4 0nc4x6rEI9ijOLxvTkariCPEIy3yGZ5NcQxZWI1XR1c6J5sD8rsB3d5HZTzsy2Ez n4NnRXw/zrIxyqLWwoYaZyfqltJdoIvE2qf9d4zMmuj0JHlW518GF7M3aXigdImt uuSqQkUJ4tadSb/UKWITqEN+F/UpaohNamnWLCbvgDl4MGJ2kGU46tC91Su4N79e iPfZ3gcyNMuRuO2i2v31OTw86TOwxGhtAJEEDvL8MRIce038fpt+QVybHUsDiGzS G9OczcysVZstfPphSzfUpMsUUUNSc5lmyskYBQV6xiqwC8VOE+bY/+ejlNm4nHQC 8Qdfqzq7sI7gXPg5yUUvc3xaT8RdT/X2FqL1B54g17pz44gDJW9LlvNXNwP0jTOm cBFvQnI1tQZRvEcqbaTO =C3n7 -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
can't see the error
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 (let [rand (new java.util.Random) nextInt (fn [a] (.nextInt rand))] ((map (print) (iterate ((nextInt dummy) 0) the error is: java.lang.ClassCastException: java.lang.Integer cannot be cast to clojure.lang.IFn (NO_SOURCE_FILE:0) why does it want to cast my 0 to a function? and how can i get rid of the dummy parameter [a]? -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOf4ZIAAoJENRtux+h35aG19UP/1tWgqcQifwUI5zHdkKWTcY8 iY9vXGEr3IvTC2nB1yXJESJ6T/4OTpGhUT9ctX+6xGxPHFC9OPUdvnp5gGUOjCFQ Qa9G8Qc6Za1uc0HFzbWYxP9yi8TAPg1WVA3RF046kKuS/m9X8uUMtCulSJH8y6m4 VmREcGlyQNjgCDMSRmMX5Y7vVuU2e6KoV6VjSopBHzX/sXBsMd0AZcnCRokBUKre 7J1PyK3YKBmRLZ6gdvnOTz4kDBoKE7yrbh2gpIsQciqsawZ0wWYlBou7JceSxtN3 Zwzm64YLxW8f6DjaRL7ZUAwTVMBkIru86hgm2bMK5pFX5f8bzBcmx09eIgd1fgLV c3bHtFYWzVrCRAGA+7iqeedQiFmkX2aK6yIcEma8KvoPXRlU5XhTiTN4B4sfPrpC qHM0U30WVIV05qs9E8rW2JDmpm1X7RpkZ9P3PEQXgYV1yJaSjPPyxRC1R0wi7f0o KUEXu+WO0egLyh3d8kfD1GMR/ztRGlS0UbJ3htqso710uD+R4GzFvRcitF99bQtm cOgz7sLB0hJTS3AblNhRzwt0CRdsPjHfBixrqbxGbXcLvkXFyoZMebuJwMZNcpzY wFhgEGyVxShXQASNub3dzNS8peU5fgoAGLexHh46e02K8a1YWjK3OOokZ3W9uCpt ghqI1/wkly1r9F/FroFo =+5YI -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
beginner question
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1
in java, i would start coding a game with a loop like this:
while (true) {
logic();
render();
}
i would store the current state of the world in an object containing
the complete data of the whole game and update its values in each
iteration.
how would i do this in clojure?
the outer loop could look like
(def next [oldstate] ()) - input = current game, return value =
next iteration
(loop [world initalState] (recur (next world))) // - the loop
but how would be world look like? the best (most trivial) thing that
i could think of is for it to be a map which is passed along several
transform functions, for example
(def playerHealthRegen [world] (...)) - input = world (a map), output
= a new map with a new entry at key playerhealth
each function would then return a slightly modified version of the
world, and at the end, i'll have my completely new state.
is that about right? or is there a completely different way i overlooked?
- --
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Re: beginner question
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1
i assumed my game to be so much fun that no one would ever want to
stop playing it.
Am 24.09.2011 22:26, schrieb Matt Hoyt:
You need a check in the loop to see if the player wants to end the
game. Clojure doesn't have a break statement like Java so you
created a infinite loop that will never end. To make sure the game
ends you need to have a base case. Example of a main game loop in
clojure:
(loop [game-state initial-state] (if (game-ends? game-state)
(close-game game-state) (recur (render (logic game-state)
You should also look into records to store the game's state.
Records are faster than hash maps and you have polymorphism with
protocols.
if i remember correctly, deftype = map, defrecord = class?
how does assoc work on records?
Be
careful of the lazy functions in clojure like map. It will only
execute when you ask a value for it.
render should do that
Matt Hoyt
*From:* Dennis Haupt d.haup...@googlemail.com
*To:* clojure@googlegroups.com *Sent:* Saturday, September 24, 2011
2:36 PM *Subject:* beginner question
in java, i would start coding a game with a loop like this: while
(true) { logic(); render(); }
i would store the current state of the world in an object
containing the complete data of the whole game and update its
values in each iteration.
how would i do this in clojure?
the outer loop could look like (def next [oldstate] ()) -
input = current game, return value = next iteration
(loop [world initalState] (recur (next world))) // - the loop
but how would be world look like? the best (most trivial) thing
that i could think of is for it to be a map which is passed along
several transform functions, for example
(def playerHealthRegen [world] (...)) - input = world (a map),
output = a new map with a new entry at key playerhealth
each function would then return a slightly modified version of the
world, and at the end, i'll have my completely new state.
is that about right? or is there a completely different way i
overlooked?
-- You received this message because you are subscribed to the
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that posts from new members are moderated - please be patient with
your first post. To unsubscribe from this group, send email to
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group at http://groups.google.com/group/clojure?hl=en
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moderated - please be patient with your first post. To unsubscribe
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Re: beginner question
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1
mutable? like in not functional?
*reading*
Am 24.09.2011 23:11, schrieb Matt Hoyt:
Both of them are java objects. Records has more default
functionality like implementing equals, hashcode, etc. You can
read more about the differences here: http://clojure.org/datatypes
assoc for records sets the value of the property for the record.
Matt Hoyt
*From:* Dennis Haupt d.haup...@googlemail.com
*To:* clojure@googlegroups.com *Sent:* Saturday, September 24, 2011
3:54 PM *Subject:* Re: beginner question
i assumed my game to be so much fun that no one would ever want to
stop playing it.
Am 24.09.2011 22:26, schrieb Matt Hoyt:
You need a check in the loop to see if the player wants to end
the game. Clojure doesn't have a break statement like Java so
you created a infinite loop that will never end. To make sure
the game ends you need to have a base case. Example of a main
game loop in clojure:
(loop [game-state initial-state] (if (game-ends? game-state)
(close-game game-state) (recur (render (logic game-state)
You should also look into records to store the game's state.
Records are faster than hash maps and you have polymorphism with
protocols.
if i remember correctly, deftype = map, defrecord = class? how does
assoc work on records?
Be
careful of the lazy functions in clojure like map. It will only
execute when you ask a value for it.
render should do that
Matt Hoyt
*From:* Dennis Haupt d.haup...@googlemail.com
mailto:d.haup...@googlemail.com
*To:* clojure@googlegroups.com mailto:clojure@googlegroups.com
*Sent:* Saturday, September 24, 2011
2:36 PM *Subject:* beginner question
in java, i would start coding a game with a loop like this:
while (true) { logic(); render(); }
i would store the current state of the world in an object
containing the complete data of the whole game and update its
values in each iteration.
how would i do this in clojure?
the outer loop could look like (def next [oldstate] ()) -
input = current game, return value = next iteration
(loop [world initalState] (recur (next world))) // - the loop
but how would be world look like? the best (most trivial)
thing that i could think of is for it to be a map which is passed
along several transform functions, for example
(def playerHealthRegen [world] (...)) - input = world (a map),
output = a new map with a new entry at key playerhealth
each function would then return a slightly modified version of
the world, and at the end, i'll have my completely new state.
is that about right? or is there a completely different way i
overlooked?
-- You received this message because you are subscribed to the
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Note
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Re: beginner question
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the website says:
deftype supports mutable fields, defrecord does not
so deftype seems to be what would be a java bean with simple
properties in java
Am 24.09.2011 23:11, schrieb Matt Hoyt:
Both of them are java objects. Records has more default
functionality like implementing equals, hashcode, etc. You can
read more about the differences here: http://clojure.org/datatypes
assoc for records sets the value of the property for the record.
Matt Hoyt
*From:* Dennis Haupt d.haup...@googlemail.com
*To:* clojure@googlegroups.com *Sent:* Saturday, September 24, 2011
3:54 PM *Subject:* Re: beginner question
i assumed my game to be so much fun that no one would ever want to
stop playing it.
Am 24.09.2011 22:26, schrieb Matt Hoyt:
You need a check in the loop to see if the player wants to end
the game. Clojure doesn't have a break statement like Java so
you created a infinite loop that will never end. To make sure
the game ends you need to have a base case. Example of a main
game loop in clojure:
(loop [game-state initial-state] (if (game-ends? game-state)
(close-game game-state) (recur (render (logic game-state)
You should also look into records to store the game's state.
Records are faster than hash maps and you have polymorphism with
protocols.
if i remember correctly, deftype = map, defrecord = class? how does
assoc work on records?
Be
careful of the lazy functions in clojure like map. It will only
execute when you ask a value for it.
render should do that
Matt Hoyt
*From:* Dennis Haupt d.haup...@googlemail.com
mailto:d.haup...@googlemail.com
*To:* clojure@googlegroups.com mailto:clojure@googlegroups.com
*Sent:* Saturday, September 24, 2011
2:36 PM *Subject:* beginner question
in java, i would start coding a game with a loop like this:
while (true) { logic(); render(); }
i would store the current state of the world in an object
containing the complete data of the whole game and update its
values in each iteration.
how would i do this in clojure?
the outer loop could look like (def next [oldstate] ()) -
input = current game, return value = next iteration
(loop [world initalState] (recur (next world))) // - the loop
but how would be world look like? the best (most trivial)
thing that i could think of is for it to be a map which is passed
along several transform functions, for example
(def playerHealthRegen [world] (...)) - input = world (a map),
output = a new map with a new entry at key playerhealth
each function would then return a slightly modified version of
the world, and at the end, i'll have my completely new state.
is that about right? or is there a completely different way i
overlooked?
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Re: advantage of dynamic typing
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Am 20.09.2011 22:55, schrieb Islon Scherer:
Scala is a OO language with FP support, clojure is a functional
language with OO support, they are very different. It's normal for
someone with a OO background to think that every method receives a
object of some kind and it's good to know it's type in advance, and
if you want polymorphism you create a subclass or implement an
interface but in clojure functions are polymorphic not classes.
Let's take the function first as an example, if you give a String
to first you'll get the first char, if you give a vector or list
you'll get the first element, if you give a java array you'll get
the element at index 0.
yes, but you magically need to know
a) for which types does it work? if you give a byte to the function,
will you get an error, or its first bit? or its first char after its
been converted to a string?
b) if i want my data structure to support this, how do i have to do that?
both questions are answered by a signature. the java one would be via
an interface, and scala offers structural types which are much more
elegant in this case:
def first[A](fromThis: {def first: A}) = fromThis.first
if that hurts, you can extract the type definition:
type SupportsFirst[A] = {
def first:A
}
def first[A](fromThis: SupportsFirst) = fromThis.first
the compiler will tell you if whatever you want to put in there
doesn't have a method first having a matching signature
In scala each collection class has a overriden first method so you
can have a static and pre-defined return type, in clojure the first
function is itself polymorphic so it doesn't make sense to say that
the return type of first is Object because it depends on the
parameter. You can code clojure's first function in scala but the
parameter and return type would be Object, and you would have to
typecast it anyway.
no, see above. i can tell scala (and even java!) to return whatever is
coming in
(Maybe with scala's extremely fancy type system you can create a
generic first function a la clojure but the type signature would
make my eyes hurt :) With doc, source (the functions) and the repl,
a static typing system would'n be that useful
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i have to object. a function signature in scala that takes something
(A) which contains something else (B) and returns such a something
else (B), for example first, would look like this:
def first[A, M[B]](fromThis:M[B]):A
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Re: advantage of dynamic typing
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Am 21.09.2011 19:58, schrieb Ken Wesson: On Wed, Sep 21, 2011 at 3:00 AM, Dennis Haupt d.haup...@googlemail.com wrote: yes, but you magically need to know a) for which types does it work? if you give a byte to the function, will you get an error, or its first bit? or its first char after its been converted to a string? b) if i want my data structure to support this, how do i have to do that? I'm curious: in what world is API documentation considered to be magical? :) - -- good point. in my experience, public apis often are well documented (no problem with clojure standard lib) while in-team-code is rarely documented at all -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOejZrAAoJENRtux+h35aGZ8gP/0sKZAOSjMLYZgD0pFy9vs5v 54wUcP9/D+YEreM8hW67P1j0lNcRqFzEjPDvGX+dykdrZKOrfQ1xpFboiARusLSn XbtoO4vlkwxwwMv9kcB6DyWtTsP7vEc9M9jJkHRNEERynk6DKBrtAX0RHXz4Qfyj uHHovEG+a68vcbrY1C9GqRck/Qqhdn0JjoKwFXkZGEUaPVf6rLRfav/JY8wl5Mj2 AKYhj/0LTUCknqkMFYkflAdLLVFjYLWX+zAeac18E2/RtRFFT5kedhYzHe3CpPY4 x6BaT5hCS/fZkyYR2kzbar1F18RL4vixmg8HbjGceLLOobW2r5EVyNRxQMv8DIpi XkjZiW0jqC6XFpoK2KVCaMzJwM46SWNoY6xYglV9/prdQ0Jmf5Isa/FVL+T24Mrq uaI6AzlKMHk4NzfQNEvJYr22q/H9oT8waEPKDMtWgQsFkSwRFotCfkqu1L5T78MT BlPek1RIZLTPjxt4kXNwdTC0Q52hiLKNNJakIEakHxSdlwmeT+1i3b+v+luFfdw6 6mGb0H8x0pUJKnU/QHFzPA/hPhg0LMOhdwTdvUm+O/7cbFhAakvhLMdUZlEmj70Y 9DugBMLto6bHyMk4kXUyHzP4ProiFmTwNE5P5UFhtl60svAmkxYuQXFl6JeisxX/ zTIgie+GRZPuGSTtcKPy =pfvF -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: advantage of dynamic typing
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Am 20.09.2011 05:43, schrieb Sean Corfield: On Mon, Sep 19, 2011 at 4:19 PM, Dennis Haupt d.haup...@googlemail.com wrote: an advantage i see is very, very concise code since you have no type annotations at all. the downside is that exactly this code might be unreadable - because you just have no idea what it uses and what it does without tests or documentation. I find Clojure code more readable because it is generic. Instead of some algorithm specialized by type, Clojure often deals with simpler generic algorithms that are applicable to a broader class of data structures which can also mean more reuse. Writing truly generic code in the presence of a strong type system is often harder word and tends to produce much more dense, more annotated code that I find harder to understand. Take a look at the documentation for the Scala collection library, for example (I'm not dissing Scala - I like Scala, but I don't think anyone will disagree that the auto-generated documentation based on the library type signatures is very hard to read, at least for the average developer). i tend to completely ignore all non-trivial type signatures and treat them as what constraints are in a database. rules that prevent me from doing things that are obviously wrong. for scala's collection framework, that is enough. i can use it perfectly well, i know exactly what it does - i just don't know *how* in detail they work. but the trivial stuff like this parameter must support method x or always returns an instance of type x really helps. - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOePUTAAoJENRtux+h35aGGHAP/j0gCcyJIBntewvQCTgaS1Xz lOj4WnrJAfMWKK/Z2r0IBgKBCI8lwqRCYvzqDMa0tVi/Lnfk8tMVMjU2x0KSX1sZ BRSoWaueQzHmnbqtCr83vfeIhz9XngmeY8b8vJ+8WjYylK2OyUlfq6I2LhR/fy1M Un8SIiMT3RtUypDdWgHBALMNXnWbw+ToHHLOKX+XpXv4FjP8G8q6g/H2vouIAt0i tCEPom2aVpGguf2f3V49jcIzU03hwKM2qfnyF4B4rejuS17kGbpBSlaavdSfQus0 sv/s14EpoIOKcIp5SQqRRE96GfmHlopshNuoB4oS3qt57oeSudI20pl/8K/zdI6y 7CajeZUA/Sl56syjTjbdq0bwOcUwWrXJVDJefJ4tgSYJu2hQnTST6NS0Op1+Mm71 nTFG4+SgEMzXoT20NGoE16wKtJn//XLkKHzQ0h/1FvSJ6pTRL/+o8hj/lDA5Y/FD qLBGaJl6z8jXB8Nltv4nTCS24ZUAn8eDOhv184OvtkTxXXu7MZnu/XPoVueRrbzP /AWLjqPwko3MdEp8/ApqtKSdZ23rW4cm5Yxo/zytCoGoDSDu7/8m5XiWKUU2Oa2R MY8EUPcRz+qawE4CaFIevzLb/EfMgJnbtvBZ9LD6VQApFweIMO1/Rc6J1rRavwps MJWJC58v8gH0AKzs0lv5 =Rlqq -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
advantage of dynamic typing
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 hi community, clojure is dynamically typed, so i thought here i might find some good reasons for that. what can you do if you sacrifice compile time type safety? an advantage i see is very, very concise code since you have no type annotations at all. the downside is that exactly this code might be unreadable - because you just have no idea what it uses and what it does without tests or documentation. another advantage are macros or macro-like constructs at compile time, for example: resultset.columnname here, columnname could be translated to resultset.getObject(columnname). you could even go a step further and use the column names as local variables. again, conciseness to the max. what else is there? is it worth sacrificing type safety? and is there no way to combine both? - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOd7HzAAoJENRtux+h35aGPfwP/iwwAdhTDfCmTzmMnp6QYnjf PEz+DDr7RxnCpTI/ptL73lSeFs2ctQGllzWgf6I2tZU+yB06ReGu/piIIZW/Z+sx 3TtIK+w9r3Jzz8lI0AljM5kfo+Zo/1OBgVaGkxon1NPbhZBnH0FpfeU43H7FnuhA 7bOu3HceOf8ju8fNNQmS+LLoueQJBEaRNn/tWkk5a/y1Ipg5hbETe/YL1+VnpAMg xyIRkfDFwtIlnZ8+0IMpdusI7PBOj+v9VINtSkAUkZptz9wvSFj4JghXU6Mw8dUp ATZSWGgdXZUrihNQ90K7OlIBG3xFrGiddSO5Gphe+PQFOwxaAf9x3z1opXVYJqt/ 7u64JHdqTQkBe4TUSEh5024CdgpLIRvXh54fthl84yjfGeodvibdEwCwg6NSF80o vl5XzeAuB/xaDkvlAE6aq2peh8+foJAxiiWoc+pKZOxYMm1lwKWTbYnnp0Slr8ym 6CB2dAX+vF/FIV3ctJvJJYcELX/ydTp0p3RoARtHD8QNebRjTlZ2VqLQqRdF1a4b Nc6tZUAmx1+zYLE+YavBIbgXwssw07MMtJfsyL4tIoX6+q7oQtsdPcVV+4/HvmcX 6d3bzdCHYod6lLcbZvBhm70DUUrxTMdF73VCvNMUwpPq9OvhRd650puMQwC+/zoK Pob2xj0YER0b1UHNKVFS =jV+l -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: small project to learn clojure
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 i DID care about my robot :) Am 17.09.2011 04:57, schrieb Alan Malloy: Notice something you do often, and try to automate it. Or find an open- source project you use, and you wish were better in some way, and improve it. Learning a language by means of I need to learn something, what should I do is not as effective, or as fun, as learning it by doing something you care about. On Sep 16, 2:50 pm, Dennis Haupt d.haup...@googlemail.com wrote: hi community, i feel compelled to do something more complex in clojure. not too big, but bigger than what fits in 100 lines and offers some chances to use macros. it should also be fun, maybe something like robocode. - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOdEvzAAoJENRtux+h35aGN8MQAI3lnLB31L1C2brCh4jgWWdo AOW+nhiF5X47ab3WPnaIrcVOkE89OBQE4/7hXlSqeJD8W6zh4uCIhkFzIKk/p9xN ISgUBues9qxh8SIhpujCgnhyp44ms8ifHzHlZIiBuR2O2+LBeYKyZIepyZCdjpcf zZ/4er3lpKB5DTwQ3X+TRAHK4zHC3eEhtSwaLki9AShw2f5abFT5H8Mo/ptSogOt lkYZHEWNHr2xShBtvJZtXfXTecRisT3Ra3ukkeAldgfRst1LXmy2G44HN1B3Cn+K 9yQJoja4aySqtEKilzADkG2+8AyNK5y2UoGjehca9omGha30KkreyNiyLws/njNn I6YGBLgzIAgcu+gXTPXqV8j0gE1YBrgTcQvzMTKlOKnA/DG0mJwJTLdfE5q6FNP5 92lAntea0fNBb5RMFpcNa4/c8lGvwgiNAJtAYeX2G1v6MFMavd1nbN/HR3fS3rLQ wpR6ssPSqjQxQZ5a0MzM/vXJX2qn8/rNqo7RkgLRMv0abOPMCA2FEtxxxsrHetkz lY/O/B+F6ByKxp5W9xdHE9f2QxfSYf9lXr0eEuHWOeJK10Jj2tYR4WmxB/s/cFNI KUGTrAeh666TTyzAq93OHLHh7y7lLXY4SwUMyOHO8t1UK0aDMlnZqRWtAHPuN3+r UF3ujhgj3WbGOeEzPEBg =ekWR -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
small project to learn clojure
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 hi community, i feel compelled to do something more complex in clojure. not too big, but bigger than what fits in 100 lines and offers some chances to use macros. it should also be fun, maybe something like robocode. - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOc8SiAAoJENRtux+h35aGh1cP/jpv1MaEES/5uTPdbDH3Sx45 hVMMC7zw6q2X1b2yEpfxSJzuDoThS7ptI2vQL2izbr9C0fwuBxuXgIXgSgLAl14S mVwnpfn5BIcuNf0QS1QfpJhCLQDJnh+EF13DKnqrNJnP9ACLJ89p8a0CB9SURFCE SgpWoTrAgNKiF1N+P9uP54N7WhwlQ20qkmn+XZDKLJWa4PFlQEpHM32rwYsYpEv8 1eM+X1xR0Z6LEKjbZGyWOShgvN2j4YdosQUWL7FQku2Z7150g13upt6nLNvF9tC6 IO+xlnJ4T68Joq8o3jOBhw+hMszQ0Ax54UfW2Q1QJjiB/E5Ex7NPhCCPdDKcQSPU YWEPHhf/ft9mXWxlEXRhLw1C0R4FwZ6OtNdMLx7X7jk/e/DCjFIxyXinyObm6BVZ sCaX4EzwA16rBeAc3D3LxMigvfm0zxEx1sp1skSyL2HQ7rNb++nR7hJjmd96yT20 MxxbIc0eTj4IZEKz+8W5U+FV7rYa11SREiDq0BBmxi1i3tJarNAAJ9I48OhOFn3y QSAT4/oblh8xa4+FgFLVnWz9rXNJMhBcgVcA1fxJLvysxG4C3MMOhVBRtR4kBt4x OcBDNn+yny4FYknxDQMo9l5VJyBuD6AlHIaKK/eBkikaX06Fwkg6/MgzwMtkJ7yR NT21x0zDCYiXdTa3SNv8 =Gqz8 -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Clojure vs Scala - anecdote
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 so the scala actors add much more overhead than the clojure equivalent? Am 07.09.2011 07:32, schrieb Sean Corfield: I just wanted to share this experience from World Singles... Back in November 2009, we started developing with Scala. We needed a long-running process that published large volumes of changes from our member database as XML packets published to a custom search engine. The mapping from half a dozen tables in the database to a flat XML schema was pretty complex and the company had tried a number of solutions with mixed success in the past. I introduced Scala based on the promises of performance, concurrency and type safety - and conciseness (especially with XML being a native data type in Scala). We've been running the Scala publishing daemons in production for most of two years. Generally they work pretty well but, under stress, they tend to hit Out of Memory exceptions and, after a lot of poking around, we became fairly convinced it was due (at least in part) to the default actor implementation in Scala. Scala is going to fold in Akka soon and we had been considering migrating to Akka anyone... But having introduced Clojure this year (after experimenting with it since about May last year), we figured we'd have a short spike to create a Clojure version of the Scala code to see how it worked out. It took about 15 hours to recreate the publishing daemon in Clojure and get it to pass all our tests. Today we ran a soak test publishing nearly 300,000 profiles in one run. The Scala code would fail with OoM exceptions if we hit it with 50,000 profiles in one run (sometimes less). The Clojure code sailed thru and is still happily running - so we'll be replacing the Scala code during our next production build. The other aspect that's interesting is that the Scala code totaled about 1,000 lines (about 31k characters of code). The Clojure replacement is just under 260 lines (around 11.5k characters of code). Neither code base has much in the way of comments (*ahem* - I'm not proud of that, just pointing out that there's no noise offsetting the code comparison). That doesn't include unit tests either, it's just the raw production code. The form of the Clojure code mostly follows the form of the Scala code, most of the same functions - it was very functional Scala - with some refactoring to helper functions to make it more modular and more maintainable. The net result is (obviously) that we'll be taking the Clojure publishing daemon to production and we'll be dropping Scala completely. Kudos to Rich Hickey and the Clojure/core team for creating a great general purpose language that can solve big problems - thank you! - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOZ6cgAAoJENRtux+h35aGsxoQAKAkmQb/8cxVsHSw1bH6mZjW Hoea0zi90eO2ds9Wk1wrFjtc0wfPPHdrp0FpZ3w1090BkwyKcRBj/iDM45sP4IY5 grc2I6vaRhfgIIVuaxgUt9HzTCbyjCOxk9xJHpCyY7sIfEIcFwNuzQWVHxgdqG/l CY/9mDe1Wex3rt2QxCSsUX/+yB5uXaxmAoX5m0jyEAmZzw/46+cVzZ8xMi9Gw1o/ mjI/mvpwTmdGcPkh7DamIEU8QjYbNBosgPWpNktJzmhtUaFdXhEMxdyDhldzUcJZ J8tZZkTWZoQqPfVdMPgfe1blDtV+nse8X2HDqed+Df42TU1YY+1VJ7e8jfr3vV62 cI+6SAqYTT91UC57GkmYKVOm01vNMpp98+fxaxBHUQi64tv/hIkWG4iHRgBCvncR hdIKfmzVwcPGrOZu6QT0RrVQzeEbz83+3l4CZQ7KOdL8k5vjd5b1T/LsPrQM1rod jDAn481tmpZKtSLe8+QbSakxfIFT9oTKUXbtDEEkN2CbJOkE4/EQwuCc/gnlo9Mr YPlPfx96JLxBfVq6JZ92VSdrpnEBS65HjKhWF587XjGjTqzYbbCNJIekwRdqga8e zkonzIj+IgnuZznV/fbKZ2yCEnO85TXoj0ZWUDnw0Ffvu2vUFvSF0ykR2BHxZBFD a1yhe/wr8AGyvIff6Hj8 =N1zz -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: coming from statically typed oo languages - how do deal with complex objects graphs in clojure?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 i tried using letfn insteaf of defn for inner functions. (def open 0) (def p1 1) (def p2 2) (def emptyfield [open open open open open open open open open]) (defn indexOf [x y] (+ x (* y 3))) (defn withmove [x,y,player,field] (assoc field (indexOf x y) player)) (defn winner [field] (letfn [(rowOwnedBy [row player] ((let [beginIndex (indexOf 0 row) currow (subvec field beginIndex (+ 3 beginIndex))] (= [player] (distinct currow))) )) (colOwnedBy [col player] ((let [beginIndex (indexOf col 0) curcol (take-nth 3 (drop beginIndex field))] (= [player] (distinct curcol))) )) (winPred [player] ((loop [cnt 0] (if (= cnt 3) false (or (rowOwnedBy cnt player) (colOwnedBy cnt player) (recur (inc cnt)))] ((let [winnerIfExists (filter winPred [p1 p2])] (if (empty? winnerIfExists) open (first winnerIfExists)) (let [moves [[0 0 p1] [1 0 p1] [2 0 p1]]] (defn fold [field nextmove] (withmove (nth nextmove 0) (nth nextmove 1) (nth nextmove 2) field)) (let [endstate (reduce fold emptyfield moves)] (println (winner endstate i'm getting an exception: Caused by: java.lang.RuntimeException: java.lang.ClassCastException: java.lang.Boolean cannot be cast to clojure.lang.IFn in this line: (= [player] (distinct currow))) why does clojure want to cast the result to IFn? Am 04.09.2011 19:57, schrieb Sergey Didenko: Dennis, may I suggest you to read this great article on Clojure: http://java.ociweb.com/mark/clojure/article.html -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOZhuaAAoJENRtux+h35aGaF0P/1xnMYA/gUuvGsBnmM5VmGBQ ncU9+3E8h4EKClatl0rdo+B4BLObYsyg7Xb3IPVdGCf5lofQVOneX2Uk41tVvM/Q E98uxotCMUjVcaOuEtLUMNBOQCy0q31erOzdKlaaecQ2KTY+GvBRRxpAbo33uqmP DaGmSiyzTGkVp9PhKcMzEjneSOagEA6oG0cOOInarfQS8Q7gQXP6Wir63kVcps72 yhtNuJmhyTOQQ7H2c+j/+mawk12YHPmD4TmLLg2/cG3ZEeaGdWS2DeWL8FVKuZ4/ grYnP1PldaOCTsrcDDCEwkM/eNxCSVqopz3LIS7oyhr8eEp9j1/Gkko56YZZYWhL ITHE083+QZ7gi/F+kQmz3Yrd8ZCeoWW7mL18d8qMppRZYlrtywwhKnFARU24VYvB hh+9Twtv22oqBnQmP3Xf2kisaFGHaf8ke1yz1upvB2L996xo/wRI7rirxWQUZtOi XLYZIowcPRf27gpTpSFplqO+92awA4pcvOgpqUuIb3FYBmSuIQI9MatQ3IzaHh9T tlF6hqFWvgkzR98CBnM2RpgE//qb0sM/DC0/lth5jUoULRN3rmpMUiSIvdwDS8TH 60ipp6IG/m8Ou+rqlEF33oPQU8DKVF26DmS5X7zWB/36VioqmuD/STov3qIabAfx Pw4JDW8nmQwcDb4gSjPI =Pw61 -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: coming from statically typed oo languages - how do deal with complex objects graphs in clojure?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 figured it out, i the () were a bit messed up. the working code: (def open 0) (def p1 1) (def p2 2) (def emptyfield [open open open open open open open open open]) (defn indexOf [x y] (+ x (* y 3))) (defn withmove [x,y,player,field] (assoc field (indexOf x y) player)) (defn winner [field] (letfn [(slashOwnedBy [player] (= [player] (distinct [(nth field 0) (nth field 4) (nth field 8)]))) (backslashOwnedBy [player] (= [player] (distinct [(nth field 2) (nth field 4) (nth field 6)]))) (rowOwnedBy [row player] (let [beginIndex (indexOf 0 row) currow (subvec field beginIndex (+ 3 beginIndex))] (= [player] (distinct currow (colOwnedBy [col player] (let [beginIndex (indexOf col 0) curcol (take-nth 3 (drop beginIndex field))] (= [player] (distinct curcol (winPred [player] (loop [cnt 0] (if (= cnt 3) (or (slashOwnedBy player) (backslashOwnedBy player)) (or (rowOwnedBy cnt player) (colOwnedBy cnt player) (recur (inc cnt))] (let [winnerIfExists (filter winPred [p1 p2])] (if (empty? winnerIfExists) open (first winnerIfExists) (let [moves [[2 0 p1] [1 1 p1] [0 2 p1]]] (defn fold [field nextmove] (withmove (nth nextmove 0) (nth nextmove 1) (nth nextmove 2) field)) (let [endstate (reduce fold emptyfield moves)] (println (winner endstate a few questions: is there a better way than (= player (distinct currow)) ? i'd like to write something like: (every? (= parameter player) currow do i have to define the function via letfn before, or is there a way to do it nested in the code? and more importantly: is there an ide that can point out syntax errors? intellij idea can detect some parentheses/braces problems, but i managed to trick it by adding too many ( and ). i got weird exceptions and had to check everything manually. Am 04.09.2011 19:57, schrieb Sergey Didenko: Dennis, may I suggest you to read this great article on Clojure: http://java.ociweb.com/mark/clojure/article.html -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOZiGMAAoJENRtux+h35aGuSwP+gPkuR9tAyHUKUhqCrkFgtiJ cuuD47EHMyws/IMwqra1RTBaCAaZbJLx9m4sFn9/KLhbGni7fzTt+zAJy1yxyW21 RaqZJC43VgG6xmDQYVt54aY9zzHz3MkI3eXZBY6Wsd0yquu2NZjnleEvoUNzwsnI nLi0nsyLkLMX6b/QdDj48XaatfeG48i5M+H9MlF7EpesoIntUEHhXRVhK1BnOeCk ctd4bo0brdszBes7UhZl9abisaiW1vf+rWAAD8HPqcFg4tWUS//SRRmFyEUJtusc GXwiPI5Meu0fKHKJv5EhQl87BD3lG+vLUn1XspYYmrZKn5G0ZxL7v/L5ol1g7Zs4 doSVsWCkR3zMwyaQgrvj/IuvIMxhWhgXGYwdEBHstPJephlwCRC5sOQCLvjwJB6H LEV0nx3m2GiWGH+jOqJ2M+j/OwsYNfPxEPRICLpUjm3lR+Whb1l+OL0fMwREgYkS ySeto5Q2pI+pkwZc1PsM2YMUEBjBToZroIlMZw6N6IUuQPFNJBcHPakRNDUs93Du nmg8kCGy+thBedbky7KxDW1bmBNFYxEWR2iASXkkIjhUdyrn3hVOxz1D1a6rM3Cb S2CdXZG5HeiCsqghyQ/m36bqlLf8CTsFz60lb4Q0Wncpn/EDTSyYq76RRPfGoMBu Nec7CzUkF8sat1lrZKxy =v1mG -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: coming from statically typed oo languages - how do deal with complex objects graphs in clojure?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 thx, that's what i figured out a moment ago. i am used to allknowing ides Am 06.09.2011 15:25, schrieb Stefan Kamphausen: hi, why does clojure want to cast the result to IFn? if I parse that correctly, you have two parens around the let-expression. That leads to Clojure evaluating the let-expression, taking the result (which is the return value of the line you mentioned: a Boolean) and trying to call that as a function. Consider: user= ((let [x :dont-care] +) 3 4) 7 Hope, this helps. Stefan -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en - -- -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOZiHUAAoJENRtux+h35aGYNEQALHei3B68cM+QR/U4pRC2FkK cKmHplrziwWcnXysac9cSC9F4mmcDw+JnnYyB4YI4pCb9El8i8E6a53J5GvilOFX xG8HF6aUxaifticyQS7kpgG47VgeoaT5VKWcpZLFqZM6axSc8MIJ2ArRNCCMZMw3 bLcTEgk0JGWqjeub2b3/pUhFWI23EaCAv4BszKCnGYqhuG847+Ks3Vd0XFO1gKAo fwEC0QipX2+0T3rrZuF3AjKQpmEN2+iEpE7sTxrgjICXbnEzGAfK395HWc0Kn8KC +IXI3K2fMkJRB3M1rqRfRf+luxbw48oPgQa/uos/iK4dPcwkODhNCQwq9PFKkNp1 W9j+rLRRm5+n3p/HfIV4GTB3skKY0ij/X00NtsrCE7OM+bs03zAj6qE5ike/bwxv XEuUSaqR1vR3LgZ5ii6OW1tev1N86cw7Mi7yQBtAFilXEZ/En5dSdEwRTVjDRSoD nL59wjTNUZUcVTpQ5I4RUTEm8LX+/5d2bU/LHYVjqV49fxY0eDF6f5eMvBXwANo5 I+l/4uf37K3TD+hXGZkh0DcPdxeyltTRoetbtx+OQg64wFxCzz6nxnOytiDInmyD +k763My95U4Ex9gIxV6r0NSoJb8hcfQEKdru1Liktghc/wMtiBWfuhgRfOO0rZU/ +oP03MYnZzFZD4Hgakz0 =+Tuc -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: coming from statically typed oo languages - how do deal with complex objects graphs in clojure?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 It was not a syntax error. Your expression just had the wrong return value. I don't see how an IDE could help here. by type inference. i don't know how far an ide could track the types in clojure since it's completely lacking any type annotations, but in scala it works really well (although it stops at method declarations, there you have to add type annotations) and such an error (returning the wrong type in a situation where it's clear what is expected) would have been highlighted at coding time (even before compilation) the ideal situation would be something like (def x [foo] (+ 5 foo)) here, the ide could look into + and check which types could be put into + without making it crash ;). that information must provided somehow (hard coded into ide, provided as parsable documentation, whatever) at all basic functions. this would enable the ide to recursively traverse the call tree and figure out what can be applied to which function. in my example, it would be x is called with a parameter foo. foo is given to + as the second parameter of a 2 parameter list. let's look into +. oh i see, it has to be a java.lang.Number. is it? yes - k. no - highlight (x param) as an error. -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOZi28AAoJENRtux+h35aGtQMQAKAemGLyIRP+6h9KaL3ix3U+ qOgupgqNGNtkDZ2ibYlYRfunJKRm8KLwVnh/0jiTBukY8ppOJTgTuUde6abcl10G pYomKWPNZBxTRAYI4nRtTKk9cEj0yx3CLYislbk4buxgmLCLNSBOLBmWBD7F8Rxz fR++KLiJJR7JJ/HszrGPr54Vo7AnI1Rfk1+FcX19UJnmIj1qdfLWq8wTSA6oy063 ZinLUBl+3OfATDJlxUMPJdPOjHMDfQ13MlksUVJq4696rhKjvVdMpIpb9REOmg/Y +ZxKVLBKr+8RruzDcUJwoiVrJOi6f1pXIMzqsKDhaqhDJwr0iHhY98SjkQBAyozI tLPQmnudMEB6gS7F2/aW2idZ9WD+XiUyoCt2FwplVJqBveBWTAUAXWdpeAl0rmVG Qjh5hiUgHs4W8X7qmlTzsZPFlwJ+rYZoHzqaw6HcWnGX9H6gv2ExM1+ELJ25dTHh 0AJZl26WLZ7eXZNAeO62FDET64RR3Oib6tVDTzP41IdLzjUx+zwFjfQFOVlEE/Cx m5azpk8d11zytG2nlcC58Yg8SBz0ZGyTtv4JJ139JqJdVzpYeol7QXZbkrgY5w3/ DQ5+bW7QjqxmD4FbjTcIDcxWcyg+SXda5p4O1ZqxQSWhNa6EzLrWPLufFBfsNyQa kUjdYxBTJkgtbhl8jxLb =6RyY -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: coming from statically typed oo languages - how do deal with complex objects graphs in clojure?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 or the equivalent shorthand form: #(= % 2) should i ever write a bigger app with clojure, it will be filled with these. i like them. -BEGIN PGP SIGNATURE- Version: GnuPG v2.0.14 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJOZi37AAoJENRtux+h35aGzQEP/RlGgWN0hRuCTBjyR7/692DH oTpAdu06MFU3jT7dPiXy1lHG/ZBZantNaHKALLKfREV+yHCnoQJUuGXRRUn1lDrF uMmMreujblbeviL9h+S0pJ9q1yTk/MH4+ceHUpM2FzPjSYpsok1OKwGFG7T2Diwb eg61TAQKV82Uwu9+06LnEwHdySs3JRfKUp4BPjGHYxXEFTQIZGVnFXbjgY5iP4xr Fi9EBZhdROF8dEk26mxWhxMLoyVx1ZdKe6bnNeAjKsTFnnnGxmot2fgtsJFxM/Rg D5bSpyEWnw6MlJgpUwDOfASCEbGDCS/oaF5pij7045apJLSVro1Py0/+D5TBiuwI OVq9mCURWeevHTISlUKHFskwJ6PlQ0rUxuXdoU+IEjdEXOw4+W9DJ4fMKk/HbDku SteyTeA3xOk4lLIIeq1t1Fhv0FwDFPisa2UcqEV6yMcrC4J9TySEnKl4hynbT+On g+VXDbTAJucCF4ltFTjPCZyAzZe5A4G6NktBlZ8NvBblERthbsLIX3JZMfoayxSv Fe5KVsrcbn88VSxVUOrZ9/RHsG+3QYsMRfRTlTCw/8hlVfP3Wg8t3ieieFVIavMg G1KwUMDDyUaeWt01BZU1c3NqA8NsjBYjukET2tnc35BKetb32I8qeRHu4W9K60Qf 9CHjRZb6IH1J1BLdKCzR =WeGr -END PGP SIGNATURE- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: coming from statically typed oo languages - how do deal with complex objects graphs in clojure?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 i started with a tic tac toe implementation, but i'm stuck: (def open 0) (def p1 1) (def p2 2) (def emptyfield [open open open open open open open open open]) (defn updated [seq index replacement] (concat (take index seq) [replacement] (drop (inc index) seq))) (defn indexOf [x y] (+ x (* y 3))) (defn withmove [x,y,player,field] (updated field (indexOf x y) player)) (defn winner [field] (defn winPred [player] (defn rowwin [row] (let [beginIndex (indexOf 0 row) currow (subvec beginIndex (+ 3 beginIndex) field)] (defn ownedByPlayer [value]) every? ownedByPlayer currow)) (defn colwin [col] (let [beginIndex (indexOf col 0) curcol (take-nth 3 (drop beginIndex field))] (defn ownedByPlayer [value]) every? ownedByPlayer curcol)) (loop [cnt 0] (if (= cnt 3) false (or (rowwin cnt) (colwin cnt) (recur (inc cnt)) (let [winnerIfExists (filter winPred [p1 p2])] (if (empty? winnerIfExists) open (first winnerIfExists (let [moves [[0 0 p1] [1 0 p1] [2 0 p1]]] (doall (for [move moves] (let [x (nth move 0) y (nth move 1) player (nth move 2)] (print player ) (print player) (print makes move at ) (print x) (print /) (println y) )) ) ) two questions: * in the last loop where i am just printing out what i want to do, i need something like foldLeft (from scala). how do i fold in clojure? * is there no predefined updated function? Am 03.09.2011 23:38, schrieb Luc Prefontaine: On Sat, 3 Sep 2011 13:43:42 -0700 (PDT) HamsterofDeath d.haup...@googlemail.com wrote: this might seem like a stupid question, but for me, not knowing the type of something is like being stuck in a dead end for anything non trivial. It's not stupid, it's normal :) In functional programming, most of the time you would like to write functions that do not need to know their arguments too intimately. You would like to work on collections, maps, ... Of course at some point you will need to write functions that will look closer to their arguments. You can pass functions to generic ones and isolate that type knowledge within them. No need to spread this everywhere. i've made a few little experiments with clojure (not much, just testing some features) and i see how powerful clojure can be - for small to medium sized problems with simple input and output - a*- pathfinding, for example. but how would i port a complex object graph (let's say 15 different classes with 3-7 fields each - person, contacts, orders, shipping details) to clojure? how would i handle it? defrecord might help you a bit here. It may feel a bit like home. defrecord fields can be referenced as map entries (:field-name ...). You can also define protocols that associated with defrecord and may ease your pain by implementing familiar functions to navigate in the hierarchy. Not sure if using a library written by someone else to handle these things is the proper thing to do right now. I feel you need to break your teeth a bit :) (It took me three months to get used to immutability :)) the main problems i see are: * do i have to actually remember the complete structure and field names and the exact spelling? using statically types languages like java or scala, the ide autocomplete features really help here. If you use obvious names that match the problem domain this should be easy to overcome. Protocols could help you here by hiding some complex navigation but please refrain implementing getters for all individual fields :)) * what about renaming a field or method? Yep of course you will not have this nice refactoring feature where you type in place the new name and get the IDE to fix this everywhere for you. But on the other hand you should have at least 10 times less code compared to java and less side effects to debug. It should not be too hard to do this using a standard text search. I use Eclipse and the straight file search. I would never exchange Clojure for Java and the automated Refactoring commands. If you encapsulate frequently exposed fields in functions you should be able to reduce the footprint of the code where these things are exposed. Hence the name changes would be easy to implement. You would confine these functions in a specific name space which decrease the like hood of missing a change. * if a function needs an instance of the root class of the complex graph above as a parameter - how do i know this at all? am i lost without good documentation of this function? in java, i just know what a method needs because it has a signature. Use the doc string when defining a fn: (defn blbl Returns the meaningful blblblbl... string. It expects a single parameter, the length of the returned string [length] ...) You
Re: coming from statically typed oo languages - how do deal with complex objects graphs in clojure?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 solved my last problem, and now i'm stucker than before: (def open 0) (def p1 1) (def p2 2) (def emptyfield [open open open open open open open open open]) (defn updated [seq index replacement] (concat (take index seq) [replacement] (drop (inc index) seq))) (defn indexOf [x y] (+ x (* y 3))) (defn withmove [x,y,player,field] (updated field (indexOf x y) player)) (defn winner [field] (defn winPred [player] (defn rowwin [row] (let [beginIndex (indexOf 0 row) currow (subvec (force field) beginIndex (+ 3 beginIndex))] (defn ownedByPlayer [value]) every? ownedByPlayer currow)) (defn colwin [col] (let [beginIndex (indexOf col 0) curcol (take-nth 3 (drop beginIndex field))] (defn ownedByPlayer [value]) every? ownedByPlayer curcol)) (loop [cnt 0] (if (= cnt 3) false (or (rowwin cnt) (colwin cnt) (recur (inc cnt)) (let [winnerIfExists (filter winPred [p1 p2])] (if (empty? winnerIfExists) open (first winnerIfExists (let [moves [[0 0 p1] [1 0 p1] [2 0 p1]]] (defn fold [field nextmove] (withmove (nth nextmove 0) (nth nextmove 1) (nth nextmove 2) field)) (let [endstate (reduce fold emptyfield moves)] (println endstate) (println (winner endstate))) ) how to convert a lazy seq into a persistent vector? Am 03.09.2011 23:38, schrieb Luc Prefontaine: On Sat, 3 Sep 2011 13:43:42 -0700 (PDT) HamsterofDeath d.haup...@googlemail.com wrote: this might seem like a stupid question, but for me, not knowing the type of something is like being stuck in a dead end for anything non trivial. It's not stupid, it's normal :) In functional programming, most of the time you would like to write functions that do not need to know their arguments too intimately. You would like to work on collections, maps, ... Of course at some point you will need to write functions that will look closer to their arguments. You can pass functions to generic ones and isolate that type knowledge within them. No need to spread this everywhere. i've made a few little experiments with clojure (not much, just testing some features) and i see how powerful clojure can be - for small to medium sized problems with simple input and output - a*- pathfinding, for example. but how would i port a complex object graph (let's say 15 different classes with 3-7 fields each - person, contacts, orders, shipping details) to clojure? how would i handle it? defrecord might help you a bit here. It may feel a bit like home. defrecord fields can be referenced as map entries (:field-name ...). You can also define protocols that associated with defrecord and may ease your pain by implementing familiar functions to navigate in the hierarchy. Not sure if using a library written by someone else to handle these things is the proper thing to do right now. I feel you need to break your teeth a bit :) (It took me three months to get used to immutability :)) the main problems i see are: * do i have to actually remember the complete structure and field names and the exact spelling? using statically types languages like java or scala, the ide autocomplete features really help here. If you use obvious names that match the problem domain this should be easy to overcome. Protocols could help you here by hiding some complex navigation but please refrain implementing getters for all individual fields :)) * what about renaming a field or method? Yep of course you will not have this nice refactoring feature where you type in place the new name and get the IDE to fix this everywhere for you. But on the other hand you should have at least 10 times less code compared to java and less side effects to debug. It should not be too hard to do this using a standard text search. I use Eclipse and the straight file search. I would never exchange Clojure for Java and the automated Refactoring commands. If you encapsulate frequently exposed fields in functions you should be able to reduce the footprint of the code where these things are exposed. Hence the name changes would be easy to implement. You would confine these functions in a specific name space which decrease the like hood of missing a change. * if a function needs an instance of the root class of the complex graph above as a parameter - how do i know this at all? am i lost without good documentation of this function? in java, i just know what a method needs because it has a signature. Use the doc string when defining a fn: (defn blbl Returns the meaningful blblblbl... string. It expects a single parameter, the length of the returned string [length] ...) You can describe the expected inputs and the result, ... Do the same thing with your name space definitions, protocols. ... It's easy, fits with your programming flow and is non-obtrusive. - -- -BEGIN
Re: coming from statically typed oo languages - how do deal with complex objects graphs in clojure?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Am 04.09.2011 19:04, schrieb Luc Prefontaine: Have a look at reduce: (reduce conj [] (take 9 (cycle [0]))) take returns a lazy seq. but reduce will return you a vector. Looks like you try to translate as if you were using a language that allows mutations no. i am trying to use the function subvec to get what would be a sublist in java. but subvec doesn't work on sequences, and what i need to quickly solve the problem would be a function that takes a sequence and returns a vector. or i could use a vector the whole time and not use a sequence at all. but you use functions to hold values that you redefine since mutation is restricted to refs and atoms. I suggest you look at atoms to hold values if they can mutate globally or at recur if you need to implement some recursion and rebind new values within a function's body. Luc P. On Sun, 04 Sep 2011 18:55:12 +0200 Dennis Haupt d.haup...@googlemail.com wrote: solved my last problem, and now i'm stucker than before: (def open 0) (def p1 1) (def p2 2) (def emptyfield [open open open open open open open open open]) (defn updated [seq index replacement] (concat (take index seq) [replacement] (drop (inc index) seq))) (defn indexOf [x y] (+ x (* y 3))) (defn withmove [x,y,player,field] (updated field (indexOf x y) player)) (defn winner [field] (defn winPred [player] (defn rowwin [row] (let [beginIndex (indexOf 0 row) currow (subvec (force field) beginIndex (+ 3 beginIndex))] (defn ownedByPlayer [value]) every? ownedByPlayer currow)) (defn colwin [col] (let [beginIndex (indexOf col 0) curcol (take-nth 3 (drop beginIndex field))] (defn ownedByPlayer [value]) every? ownedByPlayer curcol)) (loop [cnt 0] (if (= cnt 3) false (or (rowwin cnt) (colwin cnt) (recur (inc cnt)) (let [winnerIfExists (filter winPred [p1 p2])] (if (empty? winnerIfExists) open (first winnerIfExists (let [moves [[0 0 p1] [1 0 p1] [2 0 p1]]] (defn fold [field nextmove] (withmove (nth nextmove 0) (nth nextmove 1) (nth nextmove 2) field)) (let [endstate (reduce fold emptyfield moves)] (println endstate) (println (winner endstate))) ) how to convert a lazy seq into a persistent vector? Am 03.09.2011 23:38, schrieb Luc Prefontaine: On Sat, 3 Sep 2011 13:43:42 -0700 (PDT) HamsterofDeath d.haup...@googlemail.com wrote: this might seem like a stupid question, but for me, not knowing the type of something is like being stuck in a dead end for anything non trivial. It's not stupid, it's normal :) In functional programming, most of the time you would like to write functions that do not need to know their arguments too intimately. You would like to work on collections, maps, ... Of course at some point you will need to write functions that will look closer to their arguments. You can pass functions to generic ones and isolate that type knowledge within them. No need to spread this everywhere. i've made a few little experiments with clojure (not much, just testing some features) and i see how powerful clojure can be - for small to medium sized problems with simple input and output - a*- pathfinding, for example. but how would i port a complex object graph (let's say 15 different classes with 3-7 fields each - person, contacts, orders, shipping details) to clojure? how would i handle it? defrecord might help you a bit here. It may feel a bit like home. defrecord fields can be referenced as map entries (:field-name ...). You can also define protocols that associated with defrecord and may ease your pain by implementing familiar functions to navigate in the hierarchy. Not sure if using a library written by someone else to handle these things is the proper thing to do right now. I feel you need to break your teeth a bit :) (It took me three months to get used to immutability :)) the main problems i see are: * do i have to actually remember the complete structure and field names and the exact spelling? using statically types languages like java or scala, the ide autocomplete features really help here. If you use obvious names that match the problem domain this should be easy to overcome. Protocols could help you here by hiding some complex navigation but please refrain implementing getters for all individual fields :)) * what about renaming a field or method? Yep of course you will not have this nice refactoring feature where you type in place the new name and get the IDE to fix this everywhere for you. But on the other hand you should have at least 10 times less code compared to java and less side effects to debug. It should not be too hard to do this using a standard text search. I use Eclipse and the straight file search. I would never exchange Clojure for Java and the automated Refactoring commands. If you encapsulate frequently exposed fields in functions you should be able to reduce the footprint
[ANN] clojure-control 0.1.0 released.
Clojure-control is an open source clojure DSL for system admin and
deployment with many remote machines via ssh.
You can define clusters and tasks to execute repeatly,an example:
(ns samples
(:use [control.core :only [task cluster scp ssh begin]]))
(cluster :mycluster
:clients [
{ :host a.domain.com :user alogin}
{ :host b.domain.com :user blogin}
])
(task :date Get date
[]
(ssh date))
(task :deploy scp files to remote machines
[file1 file2]
(scp (file1 file2) /home/alogin/))
(begin)
More information please visit it on github
https://github.com/killme2008/clojure-control
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{ANN} clojure-control---DSL for system admin and deployment with many remote machines
1.What is clojure-control?
The idea came from node-control(https://github.com/tsmith/node-
control).
Define clusters and tasks for system administration or code
deployment, then execute them on one or many remote machines.
Clojure-control depends only on OpenSSH and clojure on the local
control machine.Remote machines simply need a standard sshd daemon.
2.Quick example
Get the current date from the two machines listed in the 'mycluster'
config with a single command:
(ns samples
(:use [control.core :only [task cluster scp ssh begin]]))
;;define clusters
(cluster :mycluster
:clients [
{ :host a.domain.com :user alogin}
{ :host b.domain.com :user blogin}
])
;;define tasks
(task :date Get date
(ssh date))
;;start running
(begin)
If saved in a file named controls.clj,run with
java -cp clojure.jar:clojure-contrib.jar:control-0.1-SNAPSHOT.jar
clojure.main controls.clj mycluster date
Each machine execute date command ,and the output form the remote
machine is printed to the console.Exmaple console output
Performing mycluster
Performing date for a.domain.com
a.domain.com:ssh: date
a.domain.com:stdout: Sun Jul 24 19:14:09 CST 2011
a.domain.com:exit: 0
Performing date for b.domain.com
b.domain.com:ssh: date
b.domain.com:stdout: Sun Jul 24 19:14:09 CST 2011
b.domain.com:exit: 0
Each line of output is labeled with the address of the machine the
command was executed on. The actual command sent and the user used to
send it is displayed. stdout and stderr output of the remote process
is identified as well as the final exit code of the local ssh
command.
3.How to scp files?
Let's define a new task named deploy
(task :deploy scp files to remote machines
(scp (release1.tar.gz release2.tar.gz) /home/alogin/))
Then it will copy release1.tar.gz and release2.tar.gz to remote
machine's /home/alogin directory.
4.More information please goto project homepage
https://github.com/killme2008/clojure-control
Any suggestion or bug reports welcomed.
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Re: {ANN} clojure-control---DSL for system admin and deployment with many remote machines
Now it's allow passing command line arguments to task now,the task
macro is changed,it must have an argument vector now:
(task :deploy deploy a file to remote machines
[file]
(scp (file) /home/user1))
And run with
clojure controls.clj deploy release.tar.gz
The release.tar.gz will be used as file argument for scp macro.
clojure-control is still on development,any suggestion welcomed.
On 7月24日, 下午9时41分, dennis killme2...@gmail.com wrote:
1.What is clojure-control?
The idea came from node-control(https://github.com/tsmith/node-
control).
Define clusters and tasks for system administration or code
deployment, then execute them on one or many remote machines.
Clojure-control depends only on OpenSSH and clojure on the local
control machine.Remote machines simply need a standard sshd daemon.
2.Quick example
Get the current date from the two machines listed in the 'mycluster'
config with a single command:
(ns samples
(:use [control.core :only [task cluster scp ssh begin]]))
;;define clusters
(cluster :mycluster
:clients [
{ :host a.domain.com :user alogin}
{ :host b.domain.com :user blogin}
])
;;define tasks
(task :date Get date
(ssh date))
;;start running
(begin)
If saved in a file named controls.clj,run with
java -cp clojure.jar:clojure-contrib.jar:control-0.1-SNAPSHOT.jar
clojure.main controls.clj mycluster date
Each machine execute date command ,and the output form the remote
machine is printed to the console.Exmaple console output
Performing mycluster
Performing date for a.domain.com
a.domain.com:ssh: date
a.domain.com:stdout: Sun Jul 24 19:14:09 CST 2011
a.domain.com:exit: 0
Performing date for b.domain.com
b.domain.com:ssh: date
b.domain.com:stdout: Sun Jul 24 19:14:09 CST 2011
b.domain.com:exit: 0
Each line of output is labeled with the address of the machine the
command was executed on. The actual command sent and the user used to
send it is displayed. stdout and stderr output of the remote process
is identified as well as the final exit code of the local ssh
command.
3.How to scp files?
Let's define a new task named deploy
(task :deploy scp files to remote machines
(scp (release1.tar.gz release2.tar.gz) /home/alogin/))
Then it will copy release1.tar.gz and release2.tar.gz to remote
machine's /home/alogin directory.
4.More information please goto project homepage
https://github.com/killme2008/clojure-control
Any suggestion or bug reports welcomed.
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Re: clearly, I'm too dense to upgrade slime/swank/clojure-mode... help?
I have a problem with swank with an upgrade recently, clojure1.3-alpha5 works, clojure-1.3alpha6 does not, to my knowledge-- which Clojure version are you using in your project? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: RabbitMQ
We did the same On Thu, Mar 24, 2011 at 10:30 AM, Mark Rathwell mark.rathw...@gmail.com wrote: I just wrapped their java client library: http://www.rabbitmq.com/java-client.html On Thu, Mar 24, 2011 at 11:15 AM, Max Weber weber.maximil...@googlemail.com wrote: What is the best Clojure library to work with RabbitMQ? Best regards Max -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Release.Next Version Number
What makes an ecosystem '1.x' vs '2.x' etc. needs to be quantifiable to make a standard out of it. To quote Peter Drucker, What gets measured gets managed. Are there any solid examples of languages that would constitute a good canonical spectrum for ecosystem versions and why? It seems like if the ecosystem surrounding a language is another concern in the semantic versioning equation that can't be sufficiently be expressed by the existing scheme, there should be a another digit(s) or a whole other semantic version system for it (e.g. 1.2.0.0 or perhaps 0.1.0_2.0.0 for Clojure 2.0 with a basic, whatever that may mean, ecosystem surrounding it.) My points may also be a moot point, since it seems to make this SemVer compatible we might have to call it SemVer 1.1.0, or 2.0 depending on how people thought the extra digit(s) would affect the compatibility with the SemVer spec as it stands. (Is it SemVer 1.0.0 right now?) All this being said, I like the idea of semantic versioning and I wish more languages/software at least attempted some sort of version number scheme transparency. #(+ 1 %) to semantic versioning. TL;DR Can an ecosystem be properly versioned? Can that version be cleanly expressed by the current SemVer scheme? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Release.Next Version Number
Inc is probably a better way to say that, yeah. I also agree with David that 2.0 has a popular connotation of shiny-ness that came with the whole infamous Web 2.0 branding phenomenon. I am now at conflict internally, because I'd like to see Clojure widely adopted, but I like the idea of the language having the agility to do radical things to make itself better in a way that Java no longer posses. So 1.3 still has its advantages. Clojure always has the choice to stay the transition to semantic versioning until Rich feels that it's at a place that semantic versioning makes sense. I believe I've thought myself in a circle and need some hammock time on this. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: ANN: A simple scheme interpreter in clojure
Thanks,it is an issue. On Jan 24, 1:09 pm, David dsieg...@yahoo.com wrote: Line 86 of core.clj is: (list 'cadr caddr) and should be: (list 'caddr caddr) On Jan 23, 9:45 pm, dennis killme2...@gmail.com wrote: I have implemented a simple interpreter in clojure,it is just transformed from the interpreter in SICP.Maybe someone interested in it. I have pushed it on github athttps://github.com/killme2008/cscheme ,you can clone and run it by yourself. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: ANN: A simple scheme interpreter in clojure
Hi, Yes,i have seen the rscheme. cscheme is just an exercise,it is not practical at all. On Jan 24, 1:44 pm, Andrzej ndrwr...@googlemail.com wrote: Hi, You may want to see if there is anything of interest for you there:http://clojure.wikidot.com/scheme-interpreter-in-clojure It has its own reader that attempts to be more compatible with Scheme than the reader used in Clojure. It constructs a fairly elaborate syntactic tree (perhaps it would be better to abstract its nodes a bit - currently it's somewhat convoluted) and preserves a lot of information about the source code in metadata. OTOH, the evaluator is AFAIR fairly buggy and incomplete. The whole thing is unmaintained now so feel free to scavenge any parts of it, if you like. Cheers, Andrzej On Mon, Jan 24, 2011 at 11:45 AM, dennis killme2...@gmail.com wrote: I have implemented a simple interpreter in clojure,it is just transformed from the interpreter in SICP.Maybe someone interested in it. I have pushed it on github at https://github.com/killme2008/cscheme ,you can clone and run it by yourself. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
ANN: A simple scheme interpreter in clojure
I have implemented a simple interpreter in clojure,it is just transformed from the interpreter in SICP.Maybe someone interested in it. I have pushed it on github at https://github.com/killme2008/cscheme ,you can clone and run it by yourself. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Vararg in protocol methods
I have defined a protocol with overload methods,and one has varargs: (ns test) (defprotocol Say (say [this a] [this a b] say hello)) (defrecord Robot [] Say (say [this a] (println (str hello, a))) (say [this a b] (println b))) Then ,i new a robot and say something: (let [ r (Robot.)] (say r dennis)) It worked and print hello,dennis,but if i passed more than one arguments,it failed: (let [ r (Robot.)] (say r dennis zhuang)) and threw exception java.lang.IllegalArgumentException: No single method: say of interface: test.Say found for function: say of protocol: Say (test.clj: 9) It seems that clojure find methods in protocol both by name and arity,and in this situation it found more than one methods named say. I don't know how to solve this problem,any suggestion? thanks a lot. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Why can not alter or ref-set ref after commute it?
Alter or ref-set a ref after commute would throw a IllegalStateException:Can't set after commute for example: user= (def counter (ref 0)) #'user/counter (dosync (commute counter inc) (ref-set counter 3)) java.lang.IllegalStateException: Can't set after commute (NO_SOURCE_FILE:0) I want to know why this should not happen?is it a explanation here? I can't understand what is the difference with commuting ref after ref- set or alter.Thanks a lot. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Improvents on agent,user-custom thread pool.
Agent use two thread pools to execute actions,send use a fixed thread pool (2+cpus threads),and send-off use a cached thread pool.These pools are global in clojure system. I think the Agent should allow users to customize the thread pool, if no custom, then use the global thread pool. Why do I need a custom thread pool? First, the default thread pool is global, send use the thread pool is a fixed size cpus +2, is likely to become the system bottleneck sometime. Although you can use the send-off, use the cache thread pool, but in a real world application, I can not use the cache thread pool, which will introduce the risk of OutOfMemoryError, normally I like to use a fixed-size thread pool. Second, the actions which global thread pool execute are from a variety of agents, the actions are not homogeneous, and can not maximize the efficient use of the thread pool, we hope that you can specify different agent to isolate a particular thread pool to maximize the use of thread pool . I think Agent could add two new functions: (set-executor! agent (java.util.concurrent.Executors/ newFixedThreadPool 2)) (shutdown-agent agent) set-executor! is to set the agent's custom thread pool,and shutdown- agent to shutdown the agent's custom thread pool. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Why can not alter or ref-set ref after commute it?
Thanks for your reply,Ulrich I knew that comute would rerun before the commit,but my problem is that if we allow ref-set ref after commuting,it seems there is no bad thing would happen.What's the purpose of this limitation except alter or ref-set have no lasting result? On Jul 25, 7:01 pm, Moritz Ulrich ulrich.mor...@googlemail.com wrote: Read the documentation of commute carefully:http://richhickey.github.com/clojure/clojure.core-api.html#clojure.co... commute acts at the end of the current dosync-block, regardless of when commute was applied inside it. That's the reason why you can't ref-set it after a commute; the commute isn't done. On Sun, Jul 25, 2010 at 11:19 AM, dennis killme2...@gmail.com wrote: Alter or ref-set a ref after commute would throw a IllegalStateException:Can't set after commute for example: user= (def counter (ref 0)) #'user/counter (dosync (commute counter inc) (ref-set counter 3)) java.lang.IllegalStateException: Can't set after commute (NO_SOURCE_FILE:0) I want to know why this should not happen?is it a explanation here? I can't understand what is the difference with commuting ref after ref- set or alter.Thanks a lot. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- Moritz Ulrich Programmer, Student, Almost normal Guy http://www.google.com/profiles/ulrich.moritz -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Memoizing a recursive function?
You should make a LazySeq to momoize intermediate result: (defn fib[n] (if ( n 2) (+ (fib (- n 2)) (fib (- n 1))) 1)) (def fib (memoize fib)) (def fib-seq (map fib (iterate inc 0))) then take the result by nth: user= (nth fib-seq 45) 1134903170 user= (nth fib-seq 46) 1836311903 user= (nth fib-seq 47) 2971215073 The only problem is that the fib-seq would cosume more memories to hold intermediate result. On Jul 22, 5:47 am, logan duskli...@gmail.com wrote: Lets say I have the following function (defn fib[n] (if ( n 2) (+ (fib (- n 2)) (fib (- n 1))) 1)) and I want to memoize it, what is the right way to do it? Using the default memoize does not work correctly. the reason is even though the first call to fib is memoized, the recursive calls go to the original fib, and not the memoized function. Even using (def fib (memoize fib)) does not seem to work. if you run (fib 45) and (fib 46), in the ideal case, (fib 47) should just call the memoized (fib 45) and (fib 46) and return almost immediately, but that is not the case. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
How to convert a list to arguments?
For example: (max 1 2 3) = 3 (max (list 1 2 3)) = (1 2 3) How to convert (list 1 2 3) to arguments for function? Thanks a lot. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Elegant way to replace a few words in string
However, in this case, the point of the code was probably to show/teach somebody how to solve a problem. When teaching, you want to make the point as clear as possible, and I think John is trying to point out, in this instance, the extra code to remove the reflection warnings detracts from that goal. I do not disagree with the idea of removing reflection warnings as a rule and not an exception, especially in production software. I should probably not fan this fire, but I did anyways... :) -- Dennis On Fri, May 28, 2010 at 2:45 PM, Laurent PETIT laurent.pe...@gmail.com wrote: 2010/5/28 Michael Gardner gardne...@gmail.com On May 28, 2010, at 12:42 PM, Laurent PETIT wrote: The rule should really always be: no warning at all (with *warn-on-reflection* set to true, of course). I strongly disagree. Why should you care about those sorts of warnings unless you've already identified a bottleneck that needs elimination? Said differently than my previous answer : consider removing warnings as the act of keeping your code in a good state/shape. I tend to not get rid of warnings enough in my own java code, but for clojure production code, I would take warnings wayy more seriously than e.g. java warnings. My 0,02€, -- Laurent -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Handling XML
Howdy, Being new to clojure, I am having a difficult time parsing XML in an elegant manner. I am pulling metric information from a ganglia server as XML and then parsing it. The below function works but it makes me feel icky. I was hoping for some tips. The dc variable contains a map with some data center information (not really interesting), and the stream variable comes from http.agent. (defn handle-xml [dc stream] (let [xml-out (xml-seq (parse (http/stream stream)))] (doseq [x xml-out] (doseq [y (:content x)] (doseq [z (:content y)] (doseq [a (:content z)] (println (:dc dc) (:NAME (:attrs z)) (:NAME (:attrs a)) (:VAL (:attrs a)) (:TN (:attrs a) The XML is of the form: ganglia multiple clusters multiple hosts multiple metrics Example of the XML: GANGLIA_XML VERSION=3.0.7 SOURCE=gmond CLUSTER NAME=cluster.example.com LOCALTIME=1258396022 OWNER=unspecified LATLONG=unspecified URL=unspecified HOST NAME=server.example.com IP=127.0.0.1 REPORTED=1258396019 TN=3 TMAX=20 DMAX=86400 LOCATION=unspe cified GMOND_STARTED=1255757736 METRIC NAME=disk_total VAL=1320.124 TYPE=double UNITS=GB TN=6684 TMAX=1200 DMAX=0 SLOPE=both SOURCE=gmond/ METRIC NAME=cpu_speed VAL=2493 TYPE=uint32 UNITS=MHz TN=682 TMAX=1200 DMAX=0 SLOPE=zero SOURCE=gmond/ ... Thanks, Dennis -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Handling XML
Thanks, I think I have the idea. (ns ziptest (:require [clojure.zip :as zip] [clojure.xml :as xml] [clojure.contrib.zip-filter :as zf]) (:use clojure.contrib.zip-filter.xml) (:import (java.io ByteArrayInputStream))) (def *xml-string* a1b1c1a1b1c1/c1c2a1b1c2/c2/b1b2c1a1b2c1/c1/b2/a1) (defn string-to-zip [s] (zip/xml-zip (xml/parse (ByteArrayInputStream. (.getBytes s) (defn parse-xml [string] (doseq [x (xml- (string-to-zip string) zf/descendants :c1)] (println --- (:content (first x) (parse-xml *xml-string*) [dr...@drowe][h:10013][J:0] ./clojure src/ziptest.clj --- [a1b1c1] --- [a1b2c1] On Wed, Dec 2, 2009 at 11:38 AM, pmf phil.fr...@gmx.de wrote: On Dec 2, 4:51 pm, Dennis shr3ks...@gmail.com wrote: The XML is of the form: ganglia multiple clusters multiple hosts multiple metrics Use XPath. Seriously, I hate XML and XSLT, but XPath is simply the most concise way to extract things from a nested structure. Most XPath- libraries allow for precompilation of XPath-expressions (similar to RegEx-precompilation) and don't require the whole XML-file to reside in memory, which makes this a nice solution for huge XML-files (though in your case this is probably no issue). To get a list of all metrics in all hosts in all clusters, you'd simply use the XPath-expression ganglia/cluster/host/metric against an XML-document; recursive fetching (if clusters could contain other clusters) could be done by using a double slash instead of a single slash. A Clojure-solution for a similar expression language would be clojure.contrib.zip-filter.xml, though I did not use it, but you might try it out. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.comclojure%2bunsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Handling XML
Thanks a bunch, this has been very helpful. -- Dennis On Wed, Dec 2, 2009 at 1:03 PM, Tayssir John Gabbour tayssir.j...@googlemail.com wrote: BTW, I should point out that zip-filter.xml/xml- is surprisingly syntaxy. (xml- loc :CLUSTER :HOST :METRIC (fn [loc] [[(xml1- (zip/up loc) (attr :NAME)) (xml1- loc (attr :NAME)) (xml1- loc (attr :VAL)) (xml1- loc (attr :TN))]])) In the above, I pass keywords, a function and calls to attr() to the xml- (and xml1-) functions. The keywords (like :CLUSTER, :HOST and :METRIC) expand into things like (tag= :CLUSTER) which return functions that operate on zipper objects. So if you're a bit overwhelmed by all the stuff that xml- accepts, just note that much of it is syntactic sugar, for your convenience. Tayssir On Dec 2, 7:41 pm, Tayssir John Gabbour tayssir.j...@googlemail.com wrote: Hi! Taking minor liberties with your code (for clarity), the following gives pretty much the same result as your handle-xml function: (ns blah (:require [clojure.xml :as xml] [clojure.zip :as zip]) (:use clojure.contrib.zip-filter.xml)) (defn my-test [] (doseq [x (xml- (zip/xml-zip (xml/parse /my-path-to/GANGLIA.xml)) :CLUSTER :HOST :METRIC (fn [loc] [[(xml1- (zip/up loc) (attr :NAME)) (xml1- loc (attr :NAME)) (xml1- loc (attr :VAL)) (xml1- loc (attr :TN))]]))] (apply println x))) The call to zip/xml-zip creates a zipper object, a simple trick to travel around xml. Each argument to xml- (after the first) drills down the tree. The last argument, once I've drilled down to the :METRIC node, collects the attributes you're interested in. The sourcecode has handy examples to play along with. For your reference: http://github.com/richhickey/clojure-contrib/blob/81b9e71effbaf6aa294... Note: If you print the zipper object, its representation will be pretty, pretty big. If that's a problem, remember to call zip/node at the end, as per the examples. Or do the crazy thing I do, which is to customize print-method (specifying each zipper object's :type metadata), so it'll have a tiny representation like: #ganglia gmond Hope that makes sense, Tayssir On Dec 2, 4:51 pm, Dennis shr3ks...@gmail.com wrote: Howdy, Being new to clojure, I am having a difficult time parsing XML in an elegant manner. I am pulling metric information from a ganglia server as XML and then parsing it. The below function works but it makes me feel icky. I was hoping for some tips. The dc variable contains a map with some data center information (not really interesting), and the stream variable comes from http.agent. (defn handle-xml [dc stream] (let [xml-out (xml-seq (parse (http/stream stream)))] (doseq [x xml-out] (doseq [y (:content x)] (doseq [z (:content y)] (doseq [a (:content z)] (println (:dc dc) (:NAME (:attrs z)) (:NAME (:attrs a)) (:VAL (:attrs a)) (:TN (:attrs a) The XML is of the form: ganglia multiple clusters multiple hosts multiple metrics Example of the XML: GANGLIA_XML VERSION=3.0.7 SOURCE=gmond CLUSTER NAME=cluster.example.com LOCALTIME=1258396022 OWNER=unspecified LATLONG=unspecified URL=unspecified HOST NAME=server.example.com IP=127.0.0.1 REPORTED=1258396019 TN=3 TMAX=20 DMAX=86400 LOCATION=unspe cified GMOND_STARTED=1255757736 METRIC NAME=disk_total VAL=1320.124 TYPE=double UNITS=GB TN=6684 TMAX=1200 DMAX=0 SLOPE=both SOURCE=gmond/ METRIC NAME=cpu_speed VAL=2493 TYPE=uint32 UNITS=MHz TN=682 TMAX=1200 DMAX=0 SLOPE=zero SOURCE=gmond/ ... Thanks, Dennis -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.comclojure%2bunsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
