From @gfldex

use v6;

class A {
  method b(){ say 'butterfly'; };
};

my $a = A.new();
my $method_ref = $a.^can('b');
$method_ref($a);

sub foo($o, $m){
  $m($o);
};

foo($a, $method_ref);

--

butterfly
Null PMC access in invoke()
  in 'foo' at line 1​:method_reference.p6
  in 'foo' at line 11​:method_reference.p6
  in main program body at line 15​:method_reference.p6

@coke - Status changed from 'new' to 'open'

From @coke

On Sat Jul 31 14​:20​:52 2010, wenzel.peppmeyer@​gmx.de wrote​:

use v6;

class A {
method b(){ say 'butterfly'; };
};

my $a = A.new();
my $method_ref = $a.^can('b');
$method_ref($a);

sub foo($o, $m){
$m($o);
};

foo($a, $method_ref);

--

butterfly
Null PMC access in invoke()
in 'foo' at line 1​:method_reference.p6
in 'foo' at line 11​:method_reference.p6
in main program body at line 15​:method_reference.p6

This no longer generates an NPA​:

Method 'postcircumfix​:<( )>' not found for invocant of class 'Parcel'
  in <anon> at src/gen/Metamodel.pm​:3164
  in block <anon> at foo​:9
  in <anon> at foo​:1

--
Will "Coke" Coleda

From @coke

On Mon Oct 03 11​:48​:33 2011, coke wrote​:

On Sat Jul 31 14​:20​:52 2010, wenzel.peppmeyer@​gmx.de wrote​:

use v6;

class A {
method b(){ say 'butterfly'; };
};

my $a = A.new();
my $method_ref = $a.^can('b');
$method_ref($a);

sub foo($o, $m){
$m($o);
};

foo($a, $method_ref);

--

butterfly
Null PMC access in invoke()
in 'foo' at line 1​:method_reference.p6
in 'foo' at line 11​:method_reference.p6
in main program body at line 15​:method_reference.p6

This no longer generates an NPA​:

Method 'postcircumfix​:<( )>' not found for invocant of class 'Parcel'
in <anon> at src/gen/Metamodel.pm​:3164
in block <anon> at foo​:9
in <anon> at foo​:1

... And is therefore (still) closable with tests.

--
Will "Coke" Coleda

From @moritz

Now tested here​:

commit 03d12d694ada66d45ca04e26ac089035b8d0f72b
Author​: Moritz Lenz <moritz@​faui2k3.org>
Date​: Thu Sep 12 21​:43​:50 2013 +0200

  RT #​76882​: calling methods with sub call syntax outside the class

S12-introspection/can.t | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)

@moritz - Status changed from 'open' to 'resolved'