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.

6.5. like(value, qr/expected regex/, name);

It is especially important when you don't want or can't realisticly expect an exact match with the result.

compares with =~

Example 6-3. examples/intro/like.t

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

use Test::More tests => 2;

like( foo(), qr/\d+/, "there are some digits in the result" );
like( bar(), qr/\d+/, "there are some digits in the result" );

sub foo {
    return "This is a long text with a number 42 in it";
}
sub bar {
    return "This is another string with no number in it";
}
$ perl like.t
1..2
ok 1 - there are some digits in the result
not ok 2 - there are some digits in the result
#   Failed test 'there are some digits in the result'
#   in like.t at line 7.
#                   'This is another string with no number in it'
#     doesn't match '(?-xism:\d+)'
# Looks like you failed 1 test of 2.

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