Your variable name say it all ;-)
It's the class/package name used with bless...

From perltoot :

To do this, all we have to do is check whether what was passed in was a reference or not. If so, we were invoked as an object method, and we need to extract the package (class) using the ref() function. If not, we just use the string passed in as the package name for blessing our referent. 
    sub new {
        my $proto = shift;
        my $class = ref($proto) || $proto;
        my $self  = {};
        $self->{NAME}   = undef;
        $self->{AGE}    = undef;
        $self->{PEERS}  = [];
        bless ($self, $class);
        return $self;
    }

[download]
 It's done this way to permit inheritance...

Check perlboot for other (good) informations...

"Only Bad Coders Code Badly In Perl" (OBC2BIP)

In reply to Re: What does the SHIFT bit do in a constructor by arhuman
in thread What does the SHIFT bit do in a constructor by Fian

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