[Haskell-cafe] Order of evaluation
cmb21 at kent.ac.uk
Thu Jul 26 12:03:31 EDT 2007
On Thu, 26 Jul 2007, Jon Harrop wrote:
> If you have a boolean-or expression:
> a || b
> will "a" be evaluated before "b" in Haskell as it is in other languages?
Yes, I believe it is defined thus:
True || _ = True
_ || True = True
_ || _ = False
Therefore it is strict in its first argument (it needs to evaluate its
first argument in order to know which pattern match to take).
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