Yes you can write a function that tells you if a given string triggers the warning. 


sub perl_thinks_it_is_number {
    eval { 
        use warnings FATAL => 'numeric';
        no warnings 'void';
        0+shift;
        1;
    }
}

print "'foo' isn't a number\n" 
    unless perl_thinks_it_is_number 'foo';

print "'17' is a number\n"
    if perl_thinks_it_is_number '17';

[download]
Note that this will consider '00' and some other oddities to be a number. You are probably better sticking with other answers elsewhere in this thread.

In reply to Re^2: check if its a number by nobull
in thread check if its a number by m.y

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