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.

7.7. Simple computation - is it really working ?

The same computation but we expect the wrong value ...

This is not that clever but I could not find a real bug in bc to show here as an example and I'd like to show what happens when the computation fails.

Example 7-3. examples/bc/bc3.pl

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

use Expect;

my $e = Expect->new;
$e->raw_pty(1);
$e->spawn("bc") or die "Cannot run bc\n";
$e->expect(1, "warranty") or die "no warranty\n";
$e->send("23+7\n");
$e->expect(1, 29) or die "no sum\n";
print "Success\n";

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