Posted below is a simple routing to determine if a number is integer. This method seems pretty straightforward, but the question of how to determine a number's 'integeriness' pops up from time to time, which leads me to believe that I'm Missing Something.
Can anyone suggest why this code would be frowned upon? 
foreach (5.6, 2, 5.000000001, 3, -2, -3, -4.12){
   print &is_int ($_)?"$_ is an integer\n":"$_ is not an integer\n";
}

sub is_int{
    my $testvar =shift;
    use integer;
    my $intval=$testvar_*1;
    no integer;
    return $testvar == $intval;
}

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2001-05-14 Edit by Corion : Moved from PMD to Seekers

In reply to Integer detection concept by boo_radley

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