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Scalar::Util provides access to the underlying Perl API looks_like_number routine which Perl itself uses internally

Perl will evaluate the string (eg) '5621hello' in numeric context as 5621 ... yet looks_like_number() will tell you that the string '5621hello' does not look like a number. That has always struck me as an anomaly .... I tend to think that a a string that "does not look like a number" should evaluate to zero in numeric context, but that (obviously) doesn't always happen.
use warnings; no warnings 'numeric'; use Scalar::Util; $string = '12.3hello'; print Scalar::Util::looks_like_number($string), "\n"; $string *= 2; print $string, "\n"; __END__ Outputs: 0 24.6
I don't think this is a big deal, btw - it's just that it doesn't DWIM (for me, anyway).

Cheers,
Rob
Update: I meant to add that this might even have some siginificance for the op - because we can't assume anything about the numeric value of a variable, based on the fact that Scalar::Util says it doesn't look like a number.

In reply to Re^2: is_numeric by syphilis
in thread is_numeric by tlm

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