Re: [OT] accessors pragma

[Damian Conway]

For what it's worth...

Perl 6 classes will autogenerate accessors that return the underlying 
attribute itself as an lvalue:

        class DogTag {
                has $.name is public;
                has $.rank is public;
                has $.serial is readonly;
                has @.medals is public;
                
                submethod BUILD ($id) { $.serial = $id }
                method title () { return "$.rank $.name" }
        }
	my $grunt = DogTag.new(71625371);

        $grunt.name = "Pyle";
        $grunt.rank = "Private";
	print "$grunt.title ($grunt.serial)\n";

And Perl 6 supports "chaining" of accessors using $_ and the unary dot 
operator, not return values:

        given $grunt {
                .name = "Patton";
                .rank = "General";
                push .medals, "Purple heart";
        }
The closest equivalent Perl 5 would be:

        package DogTag;
        
        sub new {
                my ($class, $id) = @_;
                bless { name=>undef, rank=>undef, serial=>$id, medals=>[] },
                      $class;
        }
        sub name : lvalue { $_[0]{name} }
        sub rank : lvalue { $_[0]{rank} }
        sub serial        { $_[0]{serial} }
        sub medals        { $_[0]{medals} }
        sub title { return "$_[0]{rank} $_[0]{name}" }
        
	package main;

	my $grunt = DogTag->new(71625371);

        $grunt->name = "Pyle";
        $grunt->rank = "Private";
	print $grunt->title, " (", $grunt->serial, ")\n";

And for "chaining":

        for ($grunt) {
                $_->name = "Patton";
                $_->rank = "General";
                push @{$_->medals}, "Purple heart";
        }
Damian