My main concern is not one of brevity. The return keyword does two things: it establishes the return value of the function, and it also acts as flow-control, exiting the current function.

(); is a way to set the return value of a function to nothing without using a keyword that screams out "flow-control" to readers skimming the code.

Update: As an aside, in Kavorka there is a lot of Perl code re-writing that goes on. For example, writing something like this:

method foo ($x) {
   return $x + 1;
}

[download]

Will actually be rewritten internally to something like:

sub foo {
   my $self = shift;
   my $x = @_>=1 ? shift(@_) : croak("Requires \$x");
   return $x + 1;
}

[download]

So far, so good. But what about this method: 

method bar ($x) { }

[download]

We'd expect it to return nothing. But it's rewritten to something like:

sub bar {
   my $self = shift;
   my $x = @_>=1 ? shift(@_) : croak("Requires \$x");
}

[download]

Which would actually return $x! The solution? Kavorka inserts (); into the sub body after unpacking parameters from @_. It couldn't use return because that's flow-control, and would prevent the main body of the function from executing.

use Moops; class Cow :rw { has name => (default => 'Ermintrude') }; say Cow->new->name

In reply to Re^4: Hope a subroutine will return undef by default by tobyink
in thread Hope a subroutine will return undef by default by qj1020

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