Re: Lazy evaluation?

Mirco Wahab wrote:
Michele Dondi wrote:
On Tue, 13 Feb 2007 20:14:13 -0600, Rob Hoelz <hoelz@xxxxxxxx> wrote:
local $\ = "\n";
foreach $num (1..1000_000_000) {
print $num;
}

I seem to remember that this particular one is optimized, but I'm not
really sure if up to the point of lazy evaluation.

The above (foreach list) *is* lazy evaluated (at least
in my in 5.8.8/Linux), whereas the list in

That is not lazy evaluation. Perl is just internally evaluating:

foreach $num (1..1000_000_000) {
print $num;
}

As:

for ( $num = 1; $num <= 1000_000_000; ++$num ) {
print $num;
}


Lazy evaluation would imply that the assignment to $num is delayed until it is
actually required for the print() function which is not what perl does.



John
--
Perl isn't a toolbox, but a small machine shop where you can special-order
certain sorts of tools at low cost and in short order. -- Larry Wall
.

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