So, what you're looking for is the mythical can_usefully_act_as_a_number() function. Riiiight.

The problem isn't a Perl issue. There is some very simple XS code that determines if the internal SV contains a value in the number slot. (I think this is what DBI does in its "Is it a number?" function.)

The problem is actually a semantic one. What do you consider to be a useful number? For example, why do you think Scalar::Util's function is called "looks_like_number" instead of "is_number"? It's because what one person considers a number, another person won't.

Why don't you describe what it is that determines if something can usefully act as a number? I think you'll find it a lot more difficult than you realize. And, without the requirements, writing the code is a little more difficult.

Being right, does not endow the right to be rude; politeness costs nothing.
Being unknowing, is not the same as being stupid.
Expressing a contrary opinion, whether to the individual or the group, is more often a sign of deeper thought than of cantankerous belligerence.
Do not mistake your goals as the only goals; your opinion as the only opinion; your confidence as correctness. Saying you know better is not the same as explaining you know better.

In reply to Re: Detecting if a scalar has a number or string by dragonchild
in thread Detecting if a scalar has a number or string by rrwo

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