Larry Wall must be one of the most ironic people in the open source world, on purpose or otherwise. He also made a statement like "Lua doesn't have real OO, they just use a hash with a magic function" or something like that....

The actual statement Larry Wall gave wasn't that bad...

I thought Perl 5 had an oversimplified object system till I saw Lua. In Lua, an object is just a hash, and there's a bit of syntactic sugar to call a hash element if it happens to contain code. Thats all there is. They don't even have classes. Anything resembling inheritance has to be handled by explicit delegation. That's a choice the designers of Lua made to keep the language very small and embeddable. For them, maybe it's the right choice.

ref: http://www.perl.com/pub/2007/12/06/soto-11.html

Also IIRC Wall's original Lisp quote starts with him praising Lisp and then ending with this infamous|humorous quip.

This description sounds to me almost exactly like what Perl does with it's OO (Perl's reall OO. Moose and all that are libraries built on top of Perl).

It's very similar in that they both expose the OO inner workings but after that they're quite different.

Perl requires a blessed reference (which doesn't have to be a hash but often it is the best option!) which only contains the objects state. So unlike a Lua object hash the behaviour is maintained by Perl in dynamically scoped packages/subroutines (classes/methods).

But even Perl's barebones (non-Moose) OO has inheritance. Once you add in Moose, you now have an API to your OO which is unusual.

Personally, I think Lua is amazing. Rolling your own OO system in the language itself is pretty awesome, if you like that sort of thing. Everything has to be implemented in -something-, right?

or even TMTOWTDI :)

Here in perl5i (https://metacpan.org/module/perl5i):

  func deriv ($f) {
      my $dx = 0.0001;
      func ($x) { ($f->($x + $dx) - $f->($x)) / $dx };
  }
  
  my $cube = func ($x) { $x ** 3 };
  say deriv($cube)->(2);

And also in perl6:

  sub deriv (Code $f) {
      my $dx = 0.0001;
      -> $x { ($f($x + $dx) - $f($x)) / $dx };
  }       
          
  my $cube = -> $x { $x ** 3 };
  say deriv($cube)(2);