determining if a int is a power
wolfgang at jeltsch.net
Sat Nov 8 15:17:59 EST 2003
Am Samstag, 8. November 2003, 13:13 schrieb Paul Hudak:
> But note that x `seq` x is equivalent to x, even operationally. To see why
> denotationally, note that if x evaluates to _|_, so does x `seq` x. And if
> x evaluates to a value v, so does x `seq` x. To see why operationally,
> consider the two lists:
> let x = 1+1 in [x `seq` x]
> let x = 1+1 in [x]
> Using conventional lazy evaluation in both cases, the term "1+1" is not
> evaluated until the head of the list is taken. In other words, x `seq` x in
> no way hurries the evaluation of x.
Yes, you are right.
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