Re: Moose: creating sub-classes on the fly

[ikegami]

for my $error_type (qw( Unrecoverable Unrecoverable::BrainDamage )) {
   eval("
      package MonkeyMan::Error::$error_type;
      our \@ISA = 'MonkeyMan::Error';
      1
   ")
      or die $@;
}

[McA]

I'm really interested in the question whether this straight forward solution builds up all the metaclass stuff of Moose based classes?

Best regards
McA

[ikegami]

Well, I guess that depends on how the inherited meta behaves. If you want to be sure to have all that overhead, you could use

for my $error_type (qw( Unrecoverable Unrecoverable::BrainDamage )) {
   eval("
      package MonkeyMan::Error::$error_type;
      use Moose;
      extends 'MonkeyMan::Error';
      1
   ")
      or die $@;
}

[tobyink]

As documented in Moose, you don't actually inherit the meta method from Moose::Object. Each Moose class gets its own individual meta method built for it, completely overriding any that would have been inherited.

They're all much of a muchness though:

sub meta {
    $metaclass->initialize(blessed($_[0]) || $_[0]);
}

The $metaclass variable which has been closed over is usually the string "Moose::Meta::Class", though it may be a different class name if you're doing interesting metaprogramming stuff.