[Haskell-cafe] Lazy IO and closing of file handles

Ketil Malde Ketil.Malde at bccs.uib.no
Thu Mar 15 08:01:11 EDT 2007

Matthew Brecknell wrote:
> Ketil Malde:
>> Perhaps this is an esoteric way, but I think the nicest approach is to 
>> parse into a strict structure.  If you fully evaluate each Email (or 
>> whatever structure you parse into), there will be no unevaluated thunks 
>> linking to the file, and it will be closed.
> Not necessarily so, since you are making assumptions about the
> timeliness of garbage collection. 
Good point.  I'd have hoped that the RTS would GC on file handle 
exhaustion, but perhaps this is hard to do?

I think parsing input strictly is good practice anyway, since parsing is 
often not very compute intensive, and tends to reduce the memory 
required.  At least, that is my experience.


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