You can use regexes to validate user input: 

if ($input =~ /^[0-9]+$/) {
    # work with $input here
} else {
    die "Please enter an integer\n";
}

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See also: Scalar::Util::looks_like_number

Perl 6 - second systems done right

In reply to Re: catching incorrect input type by moritz
in thread catching incorrect input type by brayk1990

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