Is there in Perl any function to determine if the contents of a string is numeric?
Something that behaves like: 

#! /usr/bin/perl
# mytest.pl
$s = shift;
if (isnumber $s) {
  print "$s is a number\n";
} else {
  print "$s isn't a number\n";
}

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Then when you call it: 

./mytest.pl 123.2
123.2 is a number

./mytest.pl aBcd
aBcd isn't a number

[download]

In reply to A function to determine if a string is numeric by juliosergio

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