From @dwarring

Rakudo is trying to import a symbol multiple times, and failing, when it
belongs to overlapping groups.

Consider 'center' in the following class definition​:

  use v6;

  class Alignment {

constant left is export(​:horizontal) = 0.0;
constant right is export(​:horizontal) = 1.0;

constant bottom is export(​:vertical) = 0.0;
constant top is export(​:vertical) = 1.0;

constant center is export(​:horizontal, :vertical) = 0.5;
  }

% perl6 -v
This is perl6 version 2013.07-12-ga1e237b built on parrot 5.5.0 revision
RELEASE_5_5_0
% perl6 -e'use Alignment :horizontal'
% perl6 -e'use Alignment :horizontal, :vertical'
===SORRY!===
Cannot import symbol center from Alignment, because it already exists in
this lexical scope
at -e​:1
------> use Alignment :horizontal, :vertical⏏<EOL>
  expecting any of​:
  pair value
  postfix

From @dwarring

Same without tabs, sorry​:

  use v6;

  class Alignment {

  constant left is export(​:horizontal) = 0.0;
  constant right is export(​:horizontal) = 1.0;

  constant bottom is export(​:vertical) = 0.0;
  constant top is export(​:vertical) = 1.0;

  constant center is export(​:horizontal, :vertical) = 0.5;
  }

From @dwarring

Another failing example​:

  use v6;

  class Test {
  sub foo is export(​:foo) {42};
  sub bar is export(​:bar) {0x42};
  sub baz is export(​:foo, :bar) {0o42};
  }

  % perl6 -e 'use Test :foo, :bar'
  ===SORRY!===
  Cannot import symbol &baz from Test, because it already exists in this
lexical scope
  ...

On Mon, Jul 22, 2013 at 3​:40 PM, perl6 via RT
<perl6-bugs-followup@​perl.org>wrote​:

Greetings,

This message has been automatically generated in response to the
creation of a trouble ticket regarding​:
"[BUG] Import of overlapping export groups",
a summary of which appears below.

There is no need to reply to this message right now. Your ticket has been
assigned an ID of [perl #​118965].

Please include the string​:

     \[perl #​118965\]

in the subject line of all future correspondence about this issue. To do
so,
you may reply to this message.

                    Thank you,
                    perl6\-bugs\-followup@​perl\.org

-------------------------------------------------------------------------
Rakudo is trying to import a symbol multiple times, and failing, when it
belongs to overlapping groups.

Consider 'center' in the following class definition​:

use v6;

class Alignment \{

constant left is export(​:horizontal) = 0.0;
constant right is export(​:horizontal) = 1.0;

constant bottom is export(​:vertical) = 0.0;
constant top is export(​:vertical) = 1.0;

constant center is export(​:horizontal, :vertical) = 0.5;
}

% perl6 -v
This is perl6 version 2013.07-12-ga1e237b built on parrot 5.5.0 revision
RELEASE_5_5_0
% perl6 -e'use Alignment :horizontal'
% perl6 -e'use Alignment :horizontal, :vertical'
===SORRY!===
Cannot import symbol center from Alignment, because it already exists in
this lexical scope
at -e​:1
------> use Alignment :horizontal, :vertical⏏<EOL>
expecting any of​:
pair value
postfix

From @moritz

Fixed with this commit​:

commit 1f1076a2facc612b67af7adfe6def5e41c8a94c0
Author​: Moritz Lenz <moritz@​faui2k3.org>
Date​: Sat Jul 27 07​:23​:17 2013 +0200

  Do not complain when exporting exactly the same symbol twice
 
  fixes RT #​118965

src/Perl6/World.nqp | 3 +++
1 files changed, 3 insertions(+), 0 deletions(-)

The RT System itself - Status changed from 'new' to 'open'

From @moritz

Tested in S11-modules/import.t

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