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[prog]

Larry Wall's Apocalypse 12 is out, finally providing Revelations to the shape that objects will take in Perl6. Word on the street is that this is the last “big” Apocalypse, and actual language implementation should actually start to happen RSN. Boy, I hope so. It's been a long wait already, and I wish Larry good health and high spirits as he & the hacksters start making this stuff happen. Peep peep peep, I await with open beak & bulging eyes.

If I may pull a pull-quote:

Before we start talking about all the hard things that should be possible,
let's look at an example of some of the easy things that should be easy.
Suppose we define a Point object that (for some strange reason) allows
you to adjust the y-axis but not the x-axis.

    class Point {
        has $.x;
        has $.y is rw;

        method clear () { $.x = 0; $.y = 0; }
    }

    my $point = Point.new(x => 2, y => 3);

    $a = $point.y;      # okay
    $point.y = 42;      # okay

    $b = $point.x;      # okay
    $point.x = -1;      # illegal, default is read-only

    $point.clear;       # reset to 0,0

If you compare that to how it would have to be written in Perl 5, you'll
note a number of differences:

• It uses the keywords class and method
  rather than package and sub.


• The attributes are named in explicit declarations rather than implicit
  hash keys.


• It is impossible to confuse the attribute variables with ordinary
  variables because of the extra dot (which also associates the attributes
  visually with method calls).


• Perhaps most importantly, we did not have to commit to using a
  hash (or any other external data structure) for the object's values.


• We didn't have to write a constructor.


• The implicit constructor automatically knows how to map named arguments
  to the attribute names.


• We didn't have to write the accessor methods.


• The accessors are by default read-only outside the class, and you
  can't get at the attributes from outside the class without an accessor.
  (Inside the class you can use the attributes directly.)


• The invocant of the clear method is implicit.


• And perhaps most obviously, Perl 6 uses . instead
  of -> to dereference an object.

Comments

[dougo.livejournal.com]

Welcome to 1967, Perl!

[prog.livejournal.com]

Now, now. Perl has been in 1967 since at least 1996.