#!/usr/bin/perl
use strict;
use warnings;

my @MessageLines = ('Message Line 1', 'Message Line 2', 'Message Line 3', 'Prompt:             ');
$MessageLines[$#MessageLines] =~ m/^(.*\S)\s+$/g;
my $Prompt = $1;
print "\$Prompt\[$Prompt\]\n";
my $CursorCol = length($Prompt);
print "\$CursorCol\[$CursorCol\]\n";