#!/usr/bin/perl -ln

use strict;
use warnings;

BEGIN { @ARGV='assign' }

our %hash;
$hash{$1}=$2 if /^(\S+)\s+(\d+)/;

END {
    my @msg=qw/FOO 1st 2nd 3rd/;
    $hash{"\$step$_"} and print $msg[$_] for 1..3;
}

__END__