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Today's Topics:
1. LTS is good but... (emacstheviking)
2. Re: LTS is good but... (emacstheviking)
3. Re: LTS is good but... (Michael Snoyman)
4. fractal x = fractal [y - head x + z | y <- x, z <- x] with
take doesnt end ('2+)
5. Re: fractal x = fractal [y - head x + z | y <- x, z <- x]
with take doesnt end (Sumit Sahrawat, Maths & Computing, IIT (BHU))
----------------------------------------------------------------------
Message: 1
Date: Tue, 3 Mar 2015 20:19:36 +0000
From: emacstheviking <[email protected]>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <[email protected]>
Subject: [Haskell-beginners] LTS is good but...
Message-ID:
<CAEiEuUKkqD6b7uz0Zb=PpJAJzG8n9US=2f3h1ml7vbtcwgk...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
I started an OpenGL project within an LTS sandbox as guided on another post
and, somewhat foolishly it would see, I did a "cabal install cabal-install"
when prompted that a new version was available.
The very next time I tried to work on my code.... I got this:
bash-3.2$ pwd
/Users/seancharles/Documents/Coding/haskell/lts1
bash-3.2$ cabal build
cabal: You need to re-run the 'configure' command. The version of Cabal
being
used has changed (was Cabal-1.20.0.1, now Cabal-1.16.0).
bash-3.2$ cabal configure
Resolving dependencies...
Configuring lts1-0.1.0.0...
cabal: At least the following dependencies are missing:
base ==4.7.*
bash-3.2$ cabal build
cabal: You need to re-run the 'configure' command. The version of Cabal
being
used has changed (was Cabal-1.20.0.1, now Cabal-1.16.0).
bash-3.2$ ls -l
total 112
-rw-r--r-- 1 seancharles staff 19 Mar 2 12:53 LICENCSE
-rw-r--r-- 1 seancharles staff 552 Mar 3 20:09 Main.hs
-rw-r--r-- 1 seancharles staff 477 Mar 3 20:07 Main.hs~
-rw-r--r-- 1 seancharles staff 46 Mar 2 12:52 Setup.hs
-rw-r--r-- 1 seancharles staff 30198 Mar 2 12:51 cabal.config
-rw-r--r-- 1 seancharles staff 1090 Mar 2 12:51 cabal.sandbox.config
drwxr-xr-x 5 seancharles staff 170 Mar 2 12:53 dist
-rw-r--r-- 1 seancharles staff 1932 Mar 2 12:52 lts1.cabal
bash-3.2$
So, welcome to a different kind of hell, "cabal version hell" perhaps?
Can anybody help me get it running again?
Thanks.
Sean.
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Message: 2
Date: Tue, 3 Mar 2015 20:20:59 +0000
From: emacstheviking <[email protected]>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <[email protected]>
Subject: Re: [Haskell-beginners] LTS is good but...
Message-ID:
<caeieuujzej4leycwb81o_crfisjux9d4abluezprbgmrgm3...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
Forgot to add that somehow, despite the upgrade, my cabal version has gone
backwards from 1.20.0.1 to 1.16.0
WTF?
On 3 March 2015 at 20:19, emacstheviking <[email protected]> wrote:
> I started an OpenGL project within an LTS sandbox as guided on another
> post and, somewhat foolishly it would see, I did a "cabal install
> cabal-install" when prompted that a new version was available.
>
> The very next time I tried to work on my code.... I got this:
>
> bash-3.2$ pwd
> /Users/seancharles/Documents/Coding/haskell/lts1
> bash-3.2$ cabal build
> cabal: You need to re-run the 'configure' command. The version of Cabal
> being
> used has changed (was Cabal-1.20.0.1, now Cabal-1.16.0).
> bash-3.2$ cabal configure
> Resolving dependencies...
> Configuring lts1-0.1.0.0...
> cabal: At least the following dependencies are missing:
> base ==4.7.*
> bash-3.2$ cabal build
> cabal: You need to re-run the 'configure' command. The version of Cabal
> being
> used has changed (was Cabal-1.20.0.1, now Cabal-1.16.0).
> bash-3.2$ ls -l
> total 112
> -rw-r--r-- 1 seancharles staff 19 Mar 2 12:53 LICENCSE
> -rw-r--r-- 1 seancharles staff 552 Mar 3 20:09 Main.hs
> -rw-r--r-- 1 seancharles staff 477 Mar 3 20:07 Main.hs~
> -rw-r--r-- 1 seancharles staff 46 Mar 2 12:52 Setup.hs
> -rw-r--r-- 1 seancharles staff 30198 Mar 2 12:51 cabal.config
> -rw-r--r-- 1 seancharles staff 1090 Mar 2 12:51 cabal.sandbox.config
> drwxr-xr-x 5 seancharles staff 170 Mar 2 12:53 dist
> -rw-r--r-- 1 seancharles staff 1932 Mar 2 12:52 lts1.cabal
> bash-3.2$
>
> So, welcome to a different kind of hell, "cabal version hell" perhaps?
>
> Can anybody help me get it running again?
> Thanks.
> Sean.
>
>
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Message: 3
Date: Tue, 03 Mar 2015 20:43:34 +0000
From: Michael Snoyman <[email protected]>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <[email protected]>
Subject: Re: [Haskell-beginners] LTS is good but...
Message-ID:
<CAKA2JgKTkTuwEA=eead2dat6xqu2pfhgovunuc+mz3e+y++...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
Funny that there's an issue being discussed in the cabal issue tracker
right now[1] similar to this. But the report you're giving here is
particularly strange. Cabal-1.16 implies that you're using GHC 7.6, which
is supported by the claim that base 4.7 isn't available. I'd recommend
starting off with running the following commands and pasting the output:
ghc --version
which ghc
cabal --version
which cabal
[1] https://github.com/haskell/cabal/issues/2438
On Tue, Mar 3, 2015 at 10:21 PM emacstheviking <[email protected]> wrote:
> Forgot to add that somehow, despite the upgrade, my cabal version has gone
> backwards from 1.20.0.1 to 1.16.0
>
> WTF?
>
>
> On 3 March 2015 at 20:19, emacstheviking <[email protected]> wrote:
>
>> I started an OpenGL project within an LTS sandbox as guided on another
>> post and, somewhat foolishly it would see, I did a "cabal install
>> cabal-install" when prompted that a new version was available.
>>
>> The very next time I tried to work on my code.... I got this:
>>
>> bash-3.2$ pwd
>> /Users/seancharles/Documents/Coding/haskell/lts1
>> bash-3.2$ cabal build
>> cabal: You need to re-run the 'configure' command. The version of Cabal
>> being
>> used has changed (was Cabal-1.20.0.1, now Cabal-1.16.0).
>> bash-3.2$ cabal configure
>> Resolving dependencies...
>> Configuring lts1-0.1.0.0...
>> cabal: At least the following dependencies are missing:
>> base ==4.7.*
>> bash-3.2$ cabal build
>> cabal: You need to re-run the 'configure' command. The version of Cabal
>> being
>> used has changed (was Cabal-1.20.0.1, now Cabal-1.16.0).
>> bash-3.2$ ls -l
>> total 112
>> -rw-r--r-- 1 seancharles staff 19 Mar 2 12:53 LICENCSE
>> -rw-r--r-- 1 seancharles staff 552 Mar 3 20:09 Main.hs
>> -rw-r--r-- 1 seancharles staff 477 Mar 3 20:07 Main.hs~
>> -rw-r--r-- 1 seancharles staff 46 Mar 2 12:52 Setup.hs
>> -rw-r--r-- 1 seancharles staff 30198 Mar 2 12:51 cabal.config
>> -rw-r--r-- 1 seancharles staff 1090 Mar 2 12:51 cabal.sandbox.config
>> drwxr-xr-x 5 seancharles staff 170 Mar 2 12:53 dist
>> -rw-r--r-- 1 seancharles staff 1932 Mar 2 12:52 lts1.cabal
>> bash-3.2$
>>
>> So, welcome to a different kind of hell, "cabal version hell" perhaps?
>>
>> Can anybody help me get it running again?
>> Thanks.
>> Sean.
>>
>>
> _______________________________________________
> Beginners mailing list
> [email protected]
> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
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Message: 4
Date: Wed, 4 Mar 2015 12:22:11 +0900
From: '2+ <[email protected]>
To: "[email protected]" <[email protected]>
Subject: [Haskell-beginners] fractal x = fractal [y - head x + z | y
<- x, z <- x] with take doesnt end
Message-ID: <[email protected]>
Content-Type: text/plain; charset=us-ascii
hi!
since my
fractal :: [Int] -> [Int]
fractal x = [y - head x + z | y <- x, z <- x]
seems to be working fine with something like:
take 300 $ cycle $ fractal $ fractal $ [11..17] ++ [55..77]
wanted to twist the function to something totally recursive
but:
fractal x = fractal [y - head x + z | y <- x, z <- x]
experimented with:
take 300 $ fractal $ [11..17] ++ [55..77]
doesnt end its process and eat up the RAM
any hints to solve this issue?
thank you
----- 2g ---
http://sarigama.namaste.jp
------------------------------
Message: 5
Date: Wed, 4 Mar 2015 09:26:08 +0530
From: "Sumit Sahrawat, Maths & Computing, IIT (BHU)"
<[email protected]>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <[email protected]>
Subject: Re: [Haskell-beginners] fractal x = fractal [y - head x + z |
y <- x, z <- x] with take doesnt end
Message-ID:
<CAJbEW8M5NrOOPTx-rv+T40FHsHXq6pyP65RZtDX=kddw2s2...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
Both the versions work for me. The one with two calls to fractal takes
~0.03 seconds, whereas the one with only one call takes ~0.01 seconds.
All timings produced using (:set +s) in ghci.
Also, that totally recursive definition is infinitely recursive.
If you provide some more context, it will be easier to answer your
question. Till now I don't exactly understand what the issue is.
On 4 March 2015 at 08:52, '2+ <[email protected]> wrote:
> hi!
> since my
>
> fractal :: [Int] -> [Int]
> fractal x = [y - head x + z | y <- x, z <- x]
>
> seems to be working fine with something like:
>
> take 300 $ cycle $ fractal $ fractal $ [11..17] ++ [55..77]
>
> wanted to twist the function to something totally recursive
> but:
>
> fractal x = fractal [y - head x + z | y <- x, z <- x]
>
> experimented with:
>
> take 300 $ fractal $ [11..17] ++ [55..77]
>
> doesnt end its process and eat up the RAM
>
> any hints to solve this issue?
>
> thank you
>
> ----- 2g ---
> http://sarigama.namaste.jp
>
>
> _______________________________________________
> Beginners mailing list
> [email protected]
> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
>
--
Regards
Sumit Sahrawat
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