For regular numbers, this is works, but it also claims 'integerness' for things like '2na' and '4ever'. Would a regexp be a reliable way of catching this, or is there something better? 
sub is_int
{
        ($_[0] =~ /^\-?\d+(?:\.\d+)?(?:e\+\d+)?$/
        && $_[0] == int $_[0]);
}

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In reply to Re^2: Integer detection concept by tadman
in thread Integer detection concept by boo_radley

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