[Haskell-cafe] Lazy problem ?

Bulat Ziganshin bulat.ziganshin at gmail.com
Fri Oct 23 03:48:31 EDT 2009

Hello zaxis,

Friday, October 23, 2009, 11:15:01 AM, you wrote:

> good_ssq_red = withFile "ssqHitNum.txt" ReadMode (\h -> do {
>         samp <- fmap str2Ints $ hGetContents h;
>         print samp;    --without this line, the result will always [1..16]
>         return $ statis samp;
>     })

withFile and hGetContents shouldn't be used together. both closes file
handle and, here, withFile closes it before hGetContents lazily reads
data. it's why you need to force reading with print

use readFile instead

Best regards,
 Bulat                            mailto:Bulat.Ziganshin at gmail.com

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