$ perldoc -q 'is a number'
Found in /usr/lib/perl5/5.6.1/pod/perlfaq4.pod
       How do I determine whether a scalar is a
       number/whole/integer/float?
...

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Not to mention `is a number' in the search box up above turns up gobs of hits.

In reply to perldoc -q redux by Fletch
in thread Regex Dollar Amounts by Additude

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