Hmm. I though lazy evaluation meant that the value wasn't calculated until needed.

If f() is a lazy evaluating function and I call it, it will give a result. The only way it wouldn't get called in the statement

result = f(a) * g(b) + h(c);
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is if the compiler took it upon itself to override my explicit request to call it. If perl ever starts doing that, I'm gonna use VB!

Hmm. I though lazy evaluation meant that the value wasn't calculated until needed.

Indeed. So, if you have:

result = f(a) * g(b) + h(c);
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and f(a) returns 0, there's no need to call g(). (Or, if you're doing Inf and NaN arithmetic, there's no need to call g() if f(a) returns NaN).

if the compiler took it upon itself to override my explicit request to call it.

If you have lazy evaluation, there's no explicit request to call anything!

What are you talking about? Are you being deliberately obtuse? The other AM already gave you examples of lazy operators which exist (Right Now! Today!) in Perl5. They're called || and &&.

Yes. They are defined as being lazy. I know they are lazy. I like that they are lazy. But now you want to make math operators lazy too?

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