# New Ticket Created by Jonathan Stowe # Please include the string: [perl #127860] # in the subject line of all future correspondence about this issue. # <URL: https://rt.perl.org/Ticket/Display.html?id=127860 >
It appears that the Metamodel::WrapDispatcher can't find the candidate to execute when the wrapped method is pre-compiled. This can be recreated in several ways, first by wrapping the method in an over-ridden add_method: lib/Vum.pm: class MetamodelX::FooHOW is Metamodel::ClassHOW { method add_method(Mu \type, $name, &code) { say "adding $name"; my &wrapper = method (|c) { say "running $name"; callsame; }; &code.wrap( &wrapper ); self.Metamodel::ClassHOW::add_method(type, $name, &code); } method compose(Mu \type) { self.Metamodel::ClassHOW::compose(type); } } my package EXPORTHOW { package SUPERSEDE { constant class = MetamodelX::FooHOW; } } And lib/Boo.pm : use Vum; #no precompilation; class Boo { has $.rabble; method rack() { say "rabble : "; } } And exercised with "perl6 -Ilib ...": use Boo; my $b = Boo.new(rabble => "hoodoo"); say $b.rack; This will fail with: Cannot invoke this object in method <anon> at /home/jonathan/devel/perl6/Vum/lib/Vum.pm (Vum) line 4 in any enter at gen/moar/m-Metamodel.nqp line 3947 in block <unit> at tt line 5 (Which points to the enter method of WrapDispatch.) Which would appear that it is not getting the appropriate Callable from .candidates[0]. With the "no precompilation" un-commented in Boo.pm this will work fine. Just to check that this wasn't something mysterious in the MOP it can also be replicated with: lib/Wom.pm: module Wom { multi sub trait_mod:<is>(Method $m, :$brapped!) is export { $m.wrap(method (|c) { say "wrapped"; callsame }); } } lib/Bok.pm: use Wom; #no precompilation; class Bok { has $.rabble; method rack() is brapped { say "rabble : "; } } And exercised with the similar script run with "perl6 -Ilib ..." : use Bok; my $b = Bok.new(rabble => "hoodoo"); say $b.rack; Then this will also fail identically without the "no precompilation". This afflicts OO::Monitors in the ecosystem which cannot be used in a module that will be precompiled, and I suspect this is also at the heart of a problem with Staticish which similarly doesn't work if used in a module which is precompiled. This is with: This is Rakudo version 2016.03-98-g61d231c built on MoarVM version 2016.03-84-g4afd7b6