You are looking at a very old, but free version of the course. If you are interesed the most recent version, check it out on the Perl Maven site.

7.16. Random and regression testing - slight improvement

Example 7-8. examples/bc/

use strict;
use warnings;

use Text::Diff;          # instead of File::Compare

# and diff instead of compare
if (my $diff = diff ("random.log", "regress.log")) {
    print "Regression failed\n\n";
    print $diff;
} else {
    print "Regression successful\n";

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