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use strict;
use warnings;
use Test::More;

sub method {
  my ($usepack, $name, $inpack, $sub) = @_;
  no strict 'refs';
  *{"${inpack}::${name}"} = $sub;
}

sub handle_method {
  my ($usepack, $use, $inpack, $name) = @_;
  return sub (&) { ($usepack, $name, $inpack, $_[0]); };
}

use Devel::Declare 'method' => \&handle_method;

BEGIN { $^H{foo} = 'bar' }

eval "method bar { 42 }";
diag $@ if $@;

is( __PACKAGE__->bar, 42 );

done_testing;