Fellow monks,

I am taking over maintenance of some Perl code which was written by a, shall we say, Perl non-expert. However, this person did have a strong C background. I believe that caused him to write a line of Perl code which currently has me baffled. Here's the relevant section:

use warnings;
use strict;

my $foo = "bar";

DoIt();

sub DoIt {
    my $it = shift // $foo;
    # Given the C background of the author, I can see why the line was
+ written as is. However, it was supposed to be
    # my $it = shift; // $foo

    print "it is '$it'\n";
}

[download]

Oddly, the output is it is 'bar', although I do not understand why. Can someone please enlighten me what the line in question actually does?

In reply to Strange syntax question by gri6507

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