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Today's Topics:
1. cabal install zlib failing (John Ky)
2. Re: Help refactor monster function (D?niel Arat?)
3. Re: Help refactor monster function (Gesh)
4. Re: cabal install zlib failing (John Ky)
----------------------------------------------------------------------
Message: 1
Date: Sun, 24 Apr 2016 13:55:08 +0000
From: John Ky <newho...@gmail.com>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <Beginners@haskell.org>
Subject: [Haskell-beginners] cabal install zlib failing
Message-ID:
<camb4o-aucxn2kd7s23vp69xyby9jyjsmzzjn2zzhdyydqnc...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
Hello Haskellers,
Does anyone know what to do in this situation?
cabal install zlib
Resolving dependencies...
Notice: installing into a sandbox located at
/home/ubuntu/hw-files/.cabal-sandbox/7.10.3
Downloading zlib-0.6.1.1...
Configuring zlib-0.6.1.1...
Failed to install zlib-0.6.1.1
Build log ( /home/ubuntu/hw-files/.cabal-sandbox/7.10.3/logs/zlib-0.6.1.1.log ):
Configuring zlib-0.6.1.1...
setup-Simple-Cabal-1.22.5.0-x86_64-linux-ghc-7.10.3: Missing dependency on a
foreign library:
* Missing (or bad) header file: zlib.h
* Missing C library: z
This problem can usually be solved by installing the system package that
provides this library (you may need the "-dev" version). If the library is
already installed but in a non-standard location then you can use the flags
--extra-include-dirs= and --extra-lib-dirs= to specify where it is.
If the header file does exist, it may contain errors that are caught by the C
compiler at the preprocessing stage. In this case you can re-run configure
with the verbosity flag -v3 to see the error messages.
cabal: Error: some packages failed to install:
zlib-0.6.1.1 failed during the configure step. The exception was:
ExitFailure 1
This is what I have in my environment:
ubuntu@box1179:~/hw-files$ dpkg -l | grep zlib
ii zlib1g
1:1.2.3.4.dfsg-3ubuntu4 compression
library - runtime
ii zlib1g:i386
1:1.2.3.4.dfsg-3ubuntu4 compression
library - runtime
iU zlib1g-dev
1:1.2.8.dfsg-1ubuntu1 compression
library - development
And this:
ubuntu@box1179:~/hw-files$ nix-env -q
cabal-install-1.22.9.0
ghc-7.10.3
nix-1.11.2
zlib-1.2.8
Cheers,
-John
?
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Message: 2
Date: Sun, 24 Apr 2016 16:41:00 +0200
From: D?niel Arat? <exitcons...@gmail.com>
To: beginners@haskell.org
Subject: Re: [Haskell-beginners] Help refactor monster function
Message-ID:
<CAHvKd2KrpKME1jB7_5EDwHzKW5nOAefwugzPtem0LGH2teU=c...@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8
>> consume f g a = foldl f a . chunk g
>> chunk g = unfoldr (fmap g . (\xs -> if null xs then Nothing else Just xs))
Wow, nice. I figured there must be a better way to express that.
>> gatherRoots = chunk (partition (compare `on` root))
That doesn't typecheck. I think you meant
> gatherRoots = chunk $ \ l@(x:_) -> partition (\y -> root x == root y) l
> P.S. You would be correct in claiming that this rewrite is too distant from
> the original to be of use. My apologies if this is the case.
No, this helps a lot, thanks! Reading pro Haskell like this helps me
improve. It's way more advanced than what I could possibly come up
with though. I'm still working my way through it.
Daniel
------------------------------
Message: 3
Date: Sun, 24 Apr 2016 20:38:37 +0300
From: Gesh <g...@gesh.uni.cx>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <beginners@haskell.org>
Subject: Re: [Haskell-beginners] Help refactor monster function
Message-ID: <f3857e8b-00ad-4815-a92b-63dc367a1...@gesh.uni.cx>
Content-Type: text/plain; charset=UTF-8
On April 24, 2016 5:41:00 PM GMT+03:00, "D?niel Arat?" <exitcons...@gmail.com>
wrote:
>>> gatherRoots = chunk (partition (compare `on` root))
>
>That doesn't typecheck. I think you meant
>> gatherRoots = chunk $ \ l@(x:_) -> partition (\y -> root x == root y)
>l
>
You are correct, that was an error in transcription.
>> P.S. You would be correct in claiming that this rewrite is too
>distant from
>> the original to be of use. My apologies if this is the case.
>
>No, this helps a lot, thanks! Reading pro Haskell like this helps me
>improve. It's way more advanced than what I could possibly come up
>with though. I'm still working my way through it.
I'm glad it helped.
Gesh
------------------------------
Message: 4
Date: Mon, 25 Apr 2016 03:41:48 +0000
From: John Ky <newho...@gmail.com>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <Beginners@haskell.org>
Subject: Re: [Haskell-beginners] cabal install zlib failing
Message-ID:
<camb4o-b9b_hc4odcrtbda3cztbwowvmd7i-swns9be5k03r...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
Hi Haskellers,
I found that this works for me:
nix-shell -p zlib --run 'cabal install zlib'
Cheers,
-John
?
On Sun, 24 Apr 2016 at 23:55 John Ky <newho...@gmail.com> wrote:
> Hello Haskellers,
>
> Does anyone know what to do in this situation?
>
> cabal install zlib
> Resolving dependencies...
> Notice: installing into a sandbox located at
> /home/ubuntu/hw-files/.cabal-sandbox/7.10.3
> Downloading zlib-0.6.1.1...
> Configuring zlib-0.6.1.1...
> Failed to install zlib-0.6.1.1
> Build log ( /home/ubuntu/hw-files/.cabal-sandbox/7.10.3/logs/zlib-0.6.1.1.log
> ):
> Configuring zlib-0.6.1.1...
> setup-Simple-Cabal-1.22.5.0-x86_64-linux-ghc-7.10.3: Missing dependency on a
> foreign library:
> * Missing (or bad) header file: zlib.h
> * Missing C library: z
> This problem can usually be solved by installing the system package that
> provides this library (you may need the "-dev" version). If the library is
> already installed but in a non-standard location then you can use the flags
> --extra-include-dirs= and --extra-lib-dirs= to specify where it is.
> If the header file does exist, it may contain errors that are caught by the C
> compiler at the preprocessing stage. In this case you can re-run configure
> with the verbosity flag -v3 to see the error messages.
> cabal: Error: some packages failed to install:
> zlib-0.6.1.1 failed during the configure step. The exception was:
> ExitFailure 1
>
> This is what I have in my environment:
>
> ubuntu@box1179:~/hw-files$ dpkg -l | grep zlib
> ii zlib1g
> 1:1.2.3.4.dfsg-3ubuntu4 compression library -
> runtime
> ii zlib1g:i386
> 1:1.2.3.4.dfsg-3ubuntu4 compression library -
> runtime
> iU zlib1g-dev
> 1:1.2.8.dfsg-1ubuntu1 compression library -
> development
>
> And this:
>
> ubuntu@box1179:~/hw-files$ nix-env -q
> cabal-install-1.22.9.0
> ghc-7.10.3
> nix-1.11.2
> zlib-1.2.8
>
> Cheers,
>
> -John
> ?
>
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