slight difference in strictness between -O0 and -O

Kirsten Chevalier catamorphism at
Mon Mar 12 17:08:00 EDT 2007

On 3/12/07, Albert Y. C. Lai <trebla at> wrote:
> main = print (map (const 'x') (take 1 (undefined:undefined)))
> In ghci, or with ghc -O0, this produces "x".
> With ghc -O, this produces Prelude.undefined.

What version of ghc?


Kirsten Chevalier* chevalier at *Often in error, never in doubt
"make them believe, if not in magic, in money well spent" -- Annie Gallup

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