in reply to Re^3: RFC: Simulating Python's @decorators in Perl with Attributes
in thread RFC: Simulating Python's @decorators in Perl with Attributes

But if you worry about name collision in UNIVERSAL (which isn't my biggest concern) why don't you just import the attribute Sorted into the current package?

Cheers Rolf

( addicted to the Perl Programming Language)

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Re^5: RFC: Simulating Python's @decorators in Perl with Attributes
by Arunbear (Prior) on Jun 02, 2013 at 18:32 UTC
    Importing the attribute does not seem to work:
    # Foo.pm package Foo; use strict; use Attribute::Handlers; use Exporter 'import'; our @EXPORT = qw/Sorted/; sub Sorted :ATTR { print "all sorted" } 1; # attr.pl #!/usr/bin/perl use strict; use warnings; use Foo; my Foo $tst1 :Sorted; my $tst2 :Sorted; print "done\n";
    It dies with
    Invalid SCALAR attribute: Sorted at /home/arun/attr.pl line 8.
      yep, tried to analyze Attribute::Handlers but no time to dig into details.

      in the meantime, here a hack that works: (plz ignore, see UPDATE)

      package Foo; use strict; use Attribute::Handlers; sub import { my $pkg = (caller)[0]; eval <<"_code_"; sub ${pkg}::Sorted :ATTR { print "all sorted" } _code_ } 1;

      #!/usr/bin/perl use strict; use warnings; use Foo; $\="\n"; my $tst2 :Sorted; print "done\n"

      Beside of this:

      I think attributes could be monkey patched to check a dedicated package like 'UNIVERSAL::attributes" for global attributes.

      Cheers Rolf

      ( addicted to the Perl Programming Language)

      UPDATE

      less hacky, more stable!

      package Foo; use strict; use Attribute::Handlers; sub import { my $src_pkg=__PACKAGE__; my $dest_pkg = (caller)[0]; my $import = "sub ${dest_pkg}::Sorted :ATTR { goto \&${src_pkg}::Sor +ted }"; eval $import; } sub Sorted { print "all sorted" } 1;

      the essential problem is that :ATTR stores the combination of package and coderef for every new attribute to be able to identify them later via findsym().