Edit file File name : underscore.pl Content :#!/usr/bin/perl use IO::Prompt; # This example demostrates how prompt autosets $_ when appropriate # Case 1... undef $_; my $first = prompt "1> "; print defined() ? "(\$_ was '$_')\n" : "(\$_ was undef)\n"; print "Got: $first\n"; # Case 2... undef $_; prompt "2> "; print defined() ? "(\$_ was '$_')\n" : "(\$_ was undef)\n"; print "Got: [$_]\n"; # Case 3... undef $_; while (prompt "3> ") { print defined() ? "(\$_ was '$_')\n" : "(\$_ was undef)\n"; print "Got: [$_]\n"; last if $_ ne "\n"; } # Case 4... undef $_; while (my $next = prompt "4> ") { print defined() ? "(\$_ was '$_')\n" : "(\$_ was undef)\n"; print "Got: $next\n"; last if $next ne "\n"; } Save