[Haskell] Probably a trivial thing for people knowing Haskell

Brandon S. Allbery KF8NH allbery at ece.cmu.edu
Sun Oct 19 11:25:21 EDT 2008


On 2008 Oct 19, at 11:18, Friedrich wrote:
> "Brandon S. Allbery KF8NH" <allbery at ece.cmu.edu> writes:
>> On 2008 Oct 19, at 2:07, Friedrich wrote:
>>> Howerver even if Strings are bad I can not see why they are hanging
>>> around so long. I open a file a read it line by line and I close the
>>> file so all read string are "garbage" and getting rid of them should
>>> not be that hard or should it?
>>
>> If your code is too lazy, you have the whole file + the close
>> operation hanging around in unevaluated thunks until you print the
>> result and it all gets processed all at once.  Laziness is a double-
>> edged sword.
> Where in my code is this laziness hidden? Is it while recurions with
> sum and count?


That would be my guess, although I'd have to examine the Core  
(intermediate compilation stage) to be certain.  Others here are  
better at looking at Haskell code and seeing where the laziness  
"leaks" are.

-- 
brandon s. allbery [solaris,freebsd,perl,pugs,haskell] allbery at kf8nh.com
system administrator [openafs,heimdal,too many hats] allbery at ece.cmu.edu
electrical and computer engineering, carnegie mellon university    KF8NH




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