while (defined($filename = $term->readline('>'))) {


##</code><code>##

use Term::ReadLine;

# Direct notation recommended over indirect notation.
my $term = Term::ReadLine->new('test');

for (;;) {
   $filename = $term->readline('>');
   die("Unable to read in filename\n")
      unless defined $filename;

   print "checking for $filename...\n";
   last if -e $filename;

   print "File not found. Please try again\n";
}

print "filename is ~~$filename~~";