shift->name

Is a lazy man's way of saying:

sub thing {
    my ($self) = @_;
    return $self->name;
}

[download]

In other words, it's a quick way of not declaring the 'self' variable. I do it a different way if I have a one line sub:

sub name {
    return $_[0]->{name};
}

[download]

...the following is equivalent:

sub name {
    return shift->{name};
}

[download]

When a Perl method receives its parameters, the first one is always the calling object. shift or $_[0] is the same thing; the object itself. If a method is more than one line, I prefer to collect the parameter as self (eg. my ($self) = @_;). That's not always the case.

Note that shift->thing; only works once... once you've shifted the object off the stack, you can't call shift again. In these cases, $_[0] is better, but if you have to use $_[0] more than once, you're far better off for self-documenting purposes to use my ($self) = @_;.

In reply to Re^3: What's the point of this 'overload' idiom? by stevieb
in thread What's the point of this 'overload' idiom? by Cody Fendant

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