I'm actually surprised there are as few "Cannot invoke this object" tickets:
https://rt.perl.org/Search/Simple.html?q=%22Cannot+invoke+this+object%2 2 A cursory survey of those would suggest that they all fall in a wider category of "code attribute of some type not surviving precompilation" On Sat, 2016-04-09 at 03:24 -0700, Lloyd Fournier via RT wrote: > For reference this is another related to: > > https://rt.perl.org/Public/Bug/Display.html?id=125634 > > On Sat, Apr 9, 2016 at 7:10 AM Jonathan Stowe <perl6-bugs-followup@pe > rl.org> > wrote: > > > > > # 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 > > > > > >
