#!/usr/bin/perl
#gives correct output for your examples

print is_numeric(10),"\n";
print is_numeric('3rd'),"\n";
print is_numeric("NA"),"\n";
print is_numeric(2.34),"\n";
print is_numeric(0.234+E06),"\n";

sub is_numeric {
no warnings;
use warnings FATAL => 'numeric';
return defined eval { $_[ 0] == 0 };
}
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