Re: Record base implementation in ClojureScript
My apologies, I just realized that there is a clojurescript group. I will ask my question there. 2015-06-15 23:02 GMT-04:00 Damien Lepage damienlep...@gmail.com: Hello, I found the following technique in order to have a record inheriting a base behavior, using extend: https://gist.github.com/david-mcneil/661983 Unfortunately this can't work in ClojureScript at this point, due to the lack of extend. Is there any alternative or should I fall back to bare functions instead of defrecord? Maybe some context on my code would help you answer this question. I transform some data through a pipeline of wrappers implementing this protocol: (defprotocol Wrapper (wrap-data [this data])) Some of my wrappers can be toggled on/off so I added this protocol: (defprotocol Togglable (toggle [this]) (on? [this])) Such a togglable wrapper would be implemented like this: (defrecord MyWrapper [on] Togglable (toggle [this] (update-in this [:on] not)) (on? [this] on) Wrapper (wrap-data [this data] (if on (do-something data) data))) Now I realized that my implementation for the Togglable protocol would always be the same, so I would have liked a way to write the code only once. The only solution I found to do that while keeping my Togglable protocol, is the following macro: (defmacro deftogglable [name fields specs] `(defrecord ~name [~@fields ~'on] ~'Togglable (~'toggle [this#] (update-in this# [:on] not)) (~'on? [~'this] ~'on) ~@specs)) Which I can use like this: (macro/deftogglable MyWrapper [] Wrapper (wrap-data [this data] (if on (do-something data) chart))) I don't like this approach too much because it's very specific and wouldn't compose well, or allow overriding part of the functions. How would you go to solve this problem? Thanks Damien -- 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 unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Record base implementation in ClojureScript
Hello, I found the following technique in order to have a record inheriting a base behavior, using extend: https://gist.github.com/david-mcneil/661983 Unfortunately this can't work in ClojureScript at this point, due to the lack of extend. Is there any alternative or should I fall back to bare functions instead of defrecord? Maybe some context on my code would help you answer this question. I transform some data through a pipeline of wrappers implementing this protocol: (defprotocol Wrapper (wrap-data [this data])) Some of my wrappers can be toggled on/off so I added this protocol: (defprotocol Togglable (toggle [this]) (on? [this])) Such a togglable wrapper would be implemented like this: (defrecord MyWrapper [on] Togglable (toggle [this] (update-in this [:on] not)) (on? [this] on) Wrapper (wrap-data [this data] (if on (do-something data) data))) Now I realized that my implementation for the Togglable protocol would always be the same, so I would have liked a way to write the code only once. The only solution I found to do that while keeping my Togglable protocol, is the following macro: (defmacro deftogglable [name fields specs] `(defrecord ~name [~@fields ~'on] ~'Togglable (~'toggle [this#] (update-in this# [:on] not)) (~'on? [~'this] ~'on) ~@specs)) Which I can use like this: (macro/deftogglable MyWrapper [] Wrapper (wrap-data [this data] (if on (do-something data) chart))) I don't like this approach too much because it's very specific and wouldn't compose well, or allow overriding part of the functions. How would you go to solve this problem? Thanks Damien -- 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 unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: Bret Victor's live editable game in ClojureScript
Awesome! Thanks for putting this together. I don't know if the most impressive is the end result or the little time you needed to code it. Both are mind blowing. 2012/2/27 Base basselh...@gmail.com Agreed. Pretty damn sweet! On Feb 27, 6:01 pm, John Szakmeister j...@szakmeister.net wrote: On Mon, Feb 27, 2012 at 3:14 PM, Chris Granger ibdk...@gmail.com wrote: Hey folks, In reference to the previous thread on Inventing On Principle, I built a ClojureScript example of his live editable game :) http://www.chris-granger.com/2012/02/26/connecting-to-your-creation/ Enjoy! Nice! You rock! -John -- 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 -- Damien Lepage http://damienlepage.com @damienlepage https://twitter.com/#!/damienlepage linkedin.com/in/damienlepage http://www.linkedin.com/in/damienlepage -- 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
Bret Victor - Inventing on Principle
Hi Everyone, You may have seen this already, if not I believe it's worth investing 1h of your life: http://vimeo.com/36579366 That's already a good candidate for the technical talk of the year, if not the decade IMO. Ok, I'm getting a bit too enthusiastic here but this is so inspiring. After watching it, you can't help thinking that we have a whole new world to invent. As a side note, you may start thinking that a REPL is not good enough. - Personal message to Laurent Petit: please watch and start thinking about CCW 1.0 ;o) - It also feels like ClojureScript is on the right path. But, most importantly, beyond any technical consideration, the last part is a great life lesson. -- Damien Lepage http://damienlepage.com @damienlepage https://twitter.com/#!/damienlepage linkedin.com/in/damienlepage http://www.linkedin.com/in/damienlepage -- 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: Bret Victor - Inventing on Principle
Sorry, I certainly didn't intend to start such a heated debate ;o) Hopefully some of you appreciate the link but you're all free to ignore. The truth is, no matter the media, there are too many interesting things and you need to choose. I had this video in my todo list for a week before I took the time to watch it. After that, I thought it was kind of special and worth sharing, any textual representation would betray its essence in my opinion. 2012/2/24 Andy Fingerhut andy.finger...@gmail.com Perhaps someone will volunteer to transcribe it and post that. You know, maybe someone who can type quickly and prefers text. :-) I've done that for one of Rich's earlier talks posted as video. It takes time, and I'm not volunteering for this one. Andy On Feb 24, 2012, at 11:57 AM, Cedric Greevey wrote: On Fri, Feb 24, 2012 at 2:51 PM, Daniel E. Renfer duck112...@gmail.com wrote: On 02/24/2012 02:42 PM, Cedric Greevey wrote: OK. I googled the group archives. Seems there was a Ken Wesson active on the list for a while, but he disappeared a couple of months before I joined. I'm not sure why people think I might be him. Ken Wesson was noted for having strong opinions as was a noted hater of videos where text will do. Most of us on this list probably have strong opinions -- it tends to go with the territory of being smarter than the average bear. As for hating videos where text will do, need I repeat my list of bullet points again? It's quite *obvious*. It's no more surprising for multiple techies to find videos-where-text-will-do to be a troubling trend than for techies to find that Lisps and even Algols are nicer languages to program large systems in than Visual Basic. :) Especially since we techies are very used to using search tools and other things specifically geared around finding *text*, and often have multiple devices including mobile where bandwidth costs can quickly become exorbitant. -- 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 -- Damien Lepage http://damienlepage.com @damienlepage https://twitter.com/#!/damienlepage linkedin.com/in/damienlepage http://www.linkedin.com/in/damienlepage -- 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: vhector 0.2
Hello, Vhector is a clojure client for the NoSQL database Apache Cassandra, wrapping the Java client Hector. It is now upgraded to work on Clojure 1.3 with Cassandra 1.0 https://github.com/damienlepage/vhector -- Damien Lepage http://damienlepage.com @damienlepage https://twitter.com/#!/damienlepage linkedin.com/in/damienlepage http://www.linkedin.com/in/damienlepage -- 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: Flattening a tree
I was looking for the exact same thing a few months ago. Take a look at this
thread:
http://groups.google.com/group/clojure/browse_thread/thread/a86d8d8c78bcab6b
2011/10/21 Timothy Baldridge tbaldri...@gmail.com
I'm a bit unsure as to the best way to solve this. Assuming I have the
following tree:
{:parent1
{:relationship1
{:child1 1}
{:child2 2}}
{:relationship2
{child3 3}}
{:_meta}}
I want to get:
[:parent1 :relationship1 :child1]
[:parent1 :relationship1 :child2]
[:parent1 :relationship2 :child3]
How do I got about getting this? Notice how I also want to filter out
all :_meta nodeswhat I want is to get a sequence of vectors where
each vector consists of all the lowest child keys along with the path
required to get to that key.
Thanks for the help,
Timothy
--
“One of the main causes of the fall of the Roman Empire was
that–lacking zero–they had no way to indicate successful termination
of their C programs.”
(Robert Firth)
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Re: is there a 4Clojure forum anywhere?
What about Google Group or Discussion Group? 2011/8/31 Alan Malloy a...@malloys.org Hey, thanks for that. I'll add a link in the next build, though I haven't decided what to call it: Forums sounds like it's part of 4clojure, Unofficial forum sounds kinda untrue if the official site is linking to it, ... Anyway, I'd appreciate having admin rights but I don't really plan to use them, and I certainly don't want exclusive rights; feel free to keep yours. On Aug 31, 11:38 am, chepprey chepp...@gmail.com wrote: ...nd now with our 2nd I need a hint! posting, I think it's time I take Alan Malloy's advice and start a forum for 4Clojure problems. May I present to you: http://groups.google.com/group/4clojure @Alan M - feel free to link to this from 4clojure.com. Also if you would like to have any sort of administrative control over the group, I'm delighted to hand any / all control over to you. I've never set up a GG before, I have no idea how much responsibility there is in owning one. @finbeu - be sure to post your Compress a sequence question! Enjoy! -chepprey On Aug 30, 11:12 am, finbeu info_pe...@t-online.de wrote: Hmm, I got stuck on the Compress a sequence. I had a look at the clojure/core.clj distinct function and I guess I have to use something similar to define my function. Or is it easier? - finbeu -- 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 -- Damien Lepage http://damienlepage.com -- 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: Vhector, client for Apache Cassandra
Hi, I just published a Clojure wrapper for the java library Hector, client for Apache Cassandra. https://github.com/damienlepage/vhector This is my first project with Clojure so the internals are certainly far from optimal. However I'm very happy with the API I've been able to put together. -- Damien Lepage http://damienlepage.com -- 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
Who's using Clojure?
Hi Everyone, I'm on a mission: introducing Clojure in my company, which is a big consulting company like many others. I started talking about Clojure to my manager yesterday. I was prepared to talk about all the technical benefits and he was interested. I still have a long way to go but I think that was a good start. However I need to figure out how to answer to one of his questions: who is using Clojure? Obviously I know each of you is using Clojure, that makes almost 5,000 people. I know there is Relevance and Clojure/core. I read about BackType or FlightCaster using Clojure. But, let's face it, that doesn't give me a killer answer. What could help is a list of success stories, a bit like MongoDB published here: http://www.mongodb.org/display/DOCS/Production+Deployments Is there a place where I could find this kind of information for Clojure? Thanks -- Damien Lepage http://damienlepage.com -- 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: Who's using Clojure?
Thanks Everyone for your input and especially to Christopher for creating the community page. I'm looking forward to read about your success stories there. 2011/4/19 Sean Allen s...@monkeysnatchbanana.com Akamai was at the conj looking to hire clojure programmers so I would assume they are as well. On Tue, Apr 19, 2011 at 10:38 AM, Damien Lepage damienlep...@gmail.com wrote: Hi Everyone, I'm on a mission: introducing Clojure in my company, which is a big consulting company like many others. I started talking about Clojure to my manager yesterday. I was prepared to talk about all the technical benefits and he was interested. I still have a long way to go but I think that was a good start. However I need to figure out how to answer to one of his questions: who is using Clojure? Obviously I know each of you is using Clojure, that makes almost 5,000 people. I know there is Relevance and Clojure/core. I read about BackType or FlightCaster using Clojure. But, let's face it, that doesn't give me a killer answer. What could help is a list of success stories, a bit like MongoDB published here: http://www.mongodb.org/display/DOCS/Production+Deployments Is there a place where I could find this kind of information for Clojure? Thanks -- Damien Lepage http://damienlepage.com -- 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 -- Damien Lepage http://damienlepage.com -- 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 this function be simpler?
Hi
I wrote a function to transform a variable number of arguments into embedded
maps.
Here is what it does:
(enmap 1 2)
{1 2}
(enmap 1 2 3)
{1 {2 3}}
(enmap 1 2 3 4)
{1 {2 {3 4}}}
(enmap 1 2 3 4 {5 6 7 8})
{1 {2 {3 {4 {5 6, 7 8}
Here is my implementation:
(defn enmap [arg args]
(if-let [more (butlast args)]
(let [k (last more), v (last args)]
(if-let [even-more (butlast more)]
(apply enmap arg (concat even-more (list (hash-map k v
(enmap arg (hash-map k v
(apply hash-map arg args)))
Two things bother me:
- Is there a way to make this function less complicated? without
recursion maybe?
- Is there something simpler than (concat even-more (list (hash-map k
v)) to append an element at the end of a sequence?
Thanks
--
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Re: Can this function be simpler?
Thanks a lot for your help, there's an awesome community here.
Sorry for the dumb questions, I'll try no to be too noisy on this list.
BTW, shouldn't it be better to create a separate mailing list for beginners?
Well, we would still need some experienced clojurers to answer the questions
though ...
Or maybe beginners like me should rather be encouraged to post their
questions on StackOverflow?
That would also give more visibility to the language (there are just about 2
or 3 questions a day about Clojure there).
What do you think? Where do you want to see my next stupid trivial question?
Damien
2011/3/10 Takahiro fat...@googlemail.com
more concise:
(defn enmap [args]
(reduce #(hash-map %2 %1) (reverse args)))
2011/3/11 Takahiro fat...@googlemail.com:
Interesting. Here is my attempt.
(defn enmap [args]
(let [[fs res] (reverse args)]
(reduce (fn [v k] (hash-map k v)) fs res)))
(enmap [1 2 3 4 {5 6 7 8}])
= {1 {2 {3 {4 {5 6, 7 8}
(let [[tail more] ((juxt last (comp reverse butlast)) [1 2 3 4 {5 6 7
8}])]
(reduce #(hash-map %2 %1) tail more))
I still cannot understand what is going on in this code. juxt always
make my head crashed.
Thanks.
2011/3/11 Damien Lepage damienlep...@gmail.com:
Hi
I wrote a function to transform a variable number of arguments into
embedded
maps.
Here is what it does:
(enmap 1 2)
{1 2}
(enmap 1 2 3)
{1 {2 3}}
(enmap 1 2 3 4)
{1 {2 {3 4}}}
(enmap 1 2 3 4 {5 6 7 8})
{1 {2 {3 {4 {5 6, 7 8}
Here is my implementation:
(defn enmap [arg args]
(if-let [more (butlast args)]
(let [k (last more), v (last args)]
(if-let [even-more (butlast more)]
(apply enmap arg (concat even-more (list (hash-map k v
(enmap arg (hash-map k v
(apply hash-map arg args)))
Two things bother me:
Is there a way to make this function less complicated? without recursion
maybe?
Is there something simpler than (concat even-more (list (hash-map k
v)) to
append an element at the end of a sequence?
Thanks
--
Damien
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Re: Transforming map entries
Hi,
I thought update-in could help but it looks as complicated as your solution:
(use 'clojure.contrib.string)
(loop [m mymap, ks (keys m)]
(let [new-m (update-in m [(first ks)] #(if (string? %) (upper-case %) %))
more (rest ks)]
(if-not (empty? more)
(recur new-m more)
new-m)))
I'm a total newbie so I may also miss an obvious and more simple solution.
2011/2/21 yair yair@gmail.com
I'm hoping this is a dumb question and I've missed something obvious.
I have a map with various key-value pairs and I want to transform some
of the values, e.g.
(def mymap {:first john :last smith :age 25}) and say I want to
change the strings to be upper case.
Right now all I can think of doing is using reduce and passing in an
empty map and the re-associating each key with the (possibly)
transformed value. Is there something like the map function that
takes two parameters, one a function that receives a pair and returns
a new pair, and the other a map, and returns a map that's
reconstituted from those pairs?
Thanks
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Re: flattening a tree
Thanks, I expected something more simple but this protocol works well.
Before I stick to it, I'm just going to give a little bit more context.
I want to write a wrapper for the Java library
Hectorhttps://github.com/rantav/hector,
client for Cassandra DB.
And this tree structure would be useful in the API.
Hector allows inserting many fields at once using the following syntax:
mutator.addInsertion(”jsmith,”
Identification,HFactory.createStringColumn(“first”, “John”))
.addInsertion(“jsmith”, “Identification”,
HFactory.createStringColumn(“last”, “Smith”))
.addInsertion(“jsmith”, “Identification”,
HFactory.createStringColumn(“middle”, “Q”))
.execute();
To avoid the repetition of key (jsmith) and column family
(“Identification”), I thought a tree structure would be nice.
Something like:
(insert! {“jsmith”
{“Identification”
{“first” “John”, “last” “Smith”, “middle” “Q”}}
{“Professional”
{“occupation” “programmer”}}})
Does it make sense to use this kind of Map here, along with the protocol
proposed by Meikel to flatten it and call the Hector API?
Would I be better with vectors or something else?
Thanks a lot
2011/2/21 Meikel Brandmeyer m...@kotka.de
Hi,
On 21 Feb., 08:17, Damien damienlep...@gmail.com wrote:
Not sure if I should talk about flattening but basically I'm trying to
achieve the following transformation:
user=(flatten-tree {1 {2 {3 4 5 6} 7 {8 9}}})
((1 2 3 4) (1 2 5 6) (1 7 8 9))
Using protocols seems overkill:
(defprotocol TreeFlattener (flatten-tree [this]))
(extend-protocol TreeFlattener
clojure.lang.IPersistentMap
(flatten-tree
[this]
(mapcat (fn [[k v]] (map #(cons k %) (flatten-tree v))) this))
Object
(flatten-tree
[this]
(list (list this)))
nil
(flatten-tree [_] (list (list nil
user= (flatten-tree {1 {2 {3 [4 nil] 5 6} 7 {8 9}}})
((1 2 3 [4 nil]) (1 2 5 6) (1 7 8 9))
... but it also allows to add other data structures later on:
(extend-type clojure.lang.IPersistentVector
TreeFlattener
(flatten-tree
[this]
(mapcat (fn [idx x] (map #(cons idx %) (flatten-tree x))) (range)
this)))
user= (flatten-tree {1 {2 {3 [4 nil] 5 6} 7 {8 9}}})
((1 2 3 0 4) (1 2 3 1 nil) (1 2 5 6) (1 7 8 9))
Beware structure depths and stack overflows, though.
Hope that helps.
Sincerely
Meikel
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Re: flattening a tree
Thanks Meikel, James and Rob for your inputs.
I'm gonna use the simple function provided by James and maybe try to come up
with a better word than flatten ;o)
2011/2/21 rob levy r.p.l...@gmail.com
That is, had flattening actually been your goal. It seem like you didn't
really want to throw out that structure, just transform it, so flattening is
irrelevant I guess other than the subject line. :)
On Mon, Feb 21, 2011 at 5:34 PM, rob levy r.p.l...@gmail.com wrote:
One way to approve the problem is to write a function to convert the
nested maps into nested seqs. Once it is in that form you can use flatten on
it and partition the flat list as you like:
(defn flatten-maptree [m]
(letfn [(maptree-seqtree
[m]
(lazy-seq
(cond
(map? m) (map #(cons
(key %)
(maptree-seqtree (val %)))
m)
:else [m])))]
(flatten (maptree-seqtree m
user= (partition 4 (flatten-maptree {1 {2 {3 4 5 6} 7 {8 9}}}))
((1 2 3 4) (5 6 7 8))
On Mon, Feb 21, 2011 at 3:25 PM, James Reeves jree...@weavejester.comwrote:
On 21 February 2011 07:17, Damien damienlep...@gmail.com wrote:
Not sure if I should talk about flattening but basically I'm trying to
achieve the following transformation:
user=(flatten-tree {1 {2 {3 4 5 6} 7 {8 9}}})
((1 2 3 4) (1 2 5 6) (1 7 8 9))
Any suggestion?
(defn flatten-tree [t]
(if (map? t)
(for [[k v] t, w (flatten-tree v)]
(cons k w))
(list (list t
In this case, I think using protocols would be over-engineering. We
can always add protocols in later if we happen to need them. That's
one of the benefits of protocols as compared to Java's interfaces.
- James
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