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Today's Topics:
1. Cannot find cause of space leak (YCH)
2. Re: Cannot find cause of space leak (Kim-Ee Yeoh)
3. Re: Cannot find cause of space leak (YCH)
4. Cabal reset/restart (Gregory Guthrie)
----------------------------------------------------------------------
Message: 1
Date: Sun, 01 Feb 2015 00:39:41 +0900
From: YCH <[email protected]>
To: haskell-beginners <[email protected]>
Subject: [Haskell-beginners] Cannot find cause of space leak
Message-ID: <2191211.qPyKtf21Jc@ych>
Content-Type: text/plain; charset="us-ascii"
Hello Haskellers,
http://lpaste.net/119693
~~~
{-# LANGUAGE TemplateHaskell #-}
import Test.Tasty
import Test.Tasty.TH
import Test.Tasty.QuickCheck
main :: IO ()
main = defaultMain tests
tests = $(testGroupGenerator)
-- Problem 15
--
-- (**) Replicate the elements of a list a given number of times.
--
-- Example:
--
-- * (repli '(a b c) 3)
-- (A A A B B B C C C)
--
-- Example in Haskell:
--
-- >>> repli "abc" 3
-- "aaabbbccc"
prop_repli xs n = a && b
where
types = ((xs::[Int]), (n::Int))
ys = repli xs n
ys' = groupByN ys n
where
groupByN [] _ = []
groupByN zs m = take m zs : groupByN (drop m zs) m
a = and $ fmap ((==n).length) ys'
b = and $ fmap f ys'
where f (x:xs) = all (==x) xs
repli :: [a] -> Int -> [a]
repli [] _ = []
repli (x:xs) n
| n <= 1 = (x:xs)
| otherwise = repli' x n ++ repli xs n
where
repli' x' 0 = []
repli' x' n' = x':repli' x' (n'-1)
~~~
> prop_repli xs n = a && b
If I set 'n' as ' n>=1', it's ok. But with just n, does not terminate.
Any advice would be appreciated.
Thanks.
--
YCH
------------------------------
Message: 2
Date: Sun, 1 Feb 2015 00:03:05 +0700
From: Kim-Ee Yeoh <[email protected]>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <[email protected]>
Subject: Re: [Haskell-beginners] Cannot find cause of space leak
Message-ID:
<CAPY+ZdTCvh3jbhH2m-=noz_gemt70mpfgpf+jd3k+azgras...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
On Sat, Jan 31, 2015 at 10:39 PM, YCH <[email protected]> wrote:
> ys' = groupByN ys n
> where
> groupByN [] _ = []
> groupByN zs m = take m zs : groupByN (drop m zs) m
>
This groupByN doesn't look like it'll terminate for negative n. So ys'
becomes an infinite list. Which causes divergence downstream.
-- Kim-Ee
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Message: 3
Date: Sun, 1 Feb 2015 02:10:00 +0900
From: YCH <[email protected]>
To: haskell-beginners <[email protected]>
Subject: Re: [Haskell-beginners] Cannot find cause of space leak
Message-ID:
<CAPtM4g=m6a3zawzjteqskclpowhwjjj_6qf_hq2jehdtgf_...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
2015. 2. 1. ?? 2:03? "Kim-Ee Yeoh" <[email protected]>?? ??:
>
>
> On Sat, Jan 31, 2015 at 10:39 PM, YCH <[email protected]> wrote:
>>
>> ys' = groupByN ys n
>> where
>> groupByN [] _ = []
>> groupByN zs m = take m zs : groupByN (drop m zs) m
>
>
> This groupByN doesn't look like it'll terminate for negative n. So ys'
becomes an infinite list. Which causes divergence downstream.
>
> -- Kim-Ee
Thanks, Kim-Ee. Now I can see.
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Message: 4
Date: Sat, 31 Jan 2015 21:13:02 -0600
From: Gregory Guthrie <[email protected]>
To: "[email protected]" <[email protected]>
Subject: [Haskell-beginners] Cabal reset/restart
Message-ID:
<[email protected]>
Content-Type: text/plain; charset="us-ascii"
I did a complete reset and restart of Haskell & Cabal, and trying to re-install
my former packages on a new clean system, most went easily but there are
already a number which would not install. (Deleted .ghc, .cabal, and .sandbox;
reinstalled Platform).
1) "ghc-pkg check" indicates a lot of issues (although most seemed to be
warnings about missing .hi or haddock html files).
Many seem to be related to looking for older versions, e.g. it complains that:
There are problems in package Win32-2.2.2.0:
Warning: library-dirs: E:\Plang\Haskell Platform\lib\Win32-2.2.2.0 doesn't
exist or isn't a directory
Warning: include-dirs: E:\Plang\Haskell Platform\lib\Win32-2.2.2.0\include
doesn't exist or isn't a directory
import-dirs: E:\Plang\Haskell Platform\lib\Win32-2.2.2.0 doesn't exist or
isn't a directory
cannot find any of
["libHSWin32-2.2.2.0.a","libHSWin32-2.2.2.0.p_a","libHSWin32-2.2.2.0-ghc7.8.3.so","libHSWin32-2.2.2.0-
ghc7.8.3.dylib","HSWin32-2.2.2.0-ghc7.8.3.dll"] on library path
And indeed it is not there, but Win32-2.3.0.2 is present, and similarly for
most all others that I see.
So why are these being reported as problems, and what to do?
2) cabal install of several of my previous packages fails; is there just some
intrinsic incompatibility of these packages, or some other error?
An example:
C:\Users\myUser\.cabal-sandbox>cabal install cgi
Resolving dependencies...
In order, the following would be installed:
exceptions-0.6.1 (reinstall) changes: mtl-2.1.3.1 -> 2.2.1,
transformers-0.3.0.0 -> 0.4.2.0
network-2.6.0.2 (new version)
cgi-3001.2.2.0 (new version)
cabal: The following packages are likely to be broken by the reinstalls:
temporary-1.2.0.3
ghc-mod-5.2.1.2
either-4.3.3
monad-journal-0.7
Use --force-reinstalls if you want to install anyway.
3) ghc-pkg check indicates a lot of broken packages for a new installation,
Although all those that I checked of these are from old versioning as above,
and there really is a good and more current version installed:
The following packages are broken, either because they have a problem listed
above, or because they depend on a broken package.
Win32-2.2.2.0
time-1.4
template-haskell-2.7.0.0
regex-base-0.93.2
process-1.1.0.1
pretty-1.1.1.0
parsec-3.1.3
old-time-1.1.0.0
old-locale-1.0.0.4
integer-gmp-0.4.0.0
HTTP-4000.2.5
hpc-0.5.1.1
hoopl-3.8.7.3
haskell98-2.0.0.1
haskell2010-1.1.0.1
haskell-platform-2012.4.0.0
ghc-prim-0.2.0.0
ghc-7.4.2
filepath-1.3.0.0
fgl-5.4.2.4
extensible-exceptions-0.1.1.4
directory-1.1.0.2
deepseq-1.3.0.0
containers-0.4.2.1
cgi-3001.1.7.4
Cabal-1.14.0
bytestring-0.9.2.1
binary-0.5.1.0
base-4.5.1.0
array-0.4.0.0
zlib-0.5.4.0
xhtml-3000.2.1
vector-0.10.0.1
transformers-0.3.0.0
text-0.11.2.3
syb-0.3.7
stm-2.4
split-0.2.1.1
regex-posix-0.95.2
regex-posix-0.95.2
regex-compat-0.95.1
regex-compat-0.95.1
random-1.0.1.1
QuickCheck-2.5.1.1
primitive-0.5.0.1
parallel-3.2.0.3
OpenGL-2.2.3.1
network-2.3.1.0
HUnit-1.2.5.1
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