From @masak

<p6eval> rakudo 99e27f​: OUTPUT«｢/foo/bar/baz/｣␤ dirname =>
｢/foo/bar/baz/｣␤ dirname => ｢/foo/bar/｣␤ basename => ｢baz｣␤␤»
<labster> okay, why do I get two copies of dirname when the match only
succeeds once?
<masak> huuhhnn.
<masak> wut.
<masak> I suspect a backtracking-related glitch.
* masak submits labster's rakudobug
<masak> r​: say ('/foo/bar/baz/' ~~ m/^ $<dirname>=(.* '/'+)?
$<basename>=(<-[\/]>+) '/'* $ /).keys
<p6eval> rakudo 99e27f​: OUTPUT«dirname basename␤»
<masak> labster​: .gist shows double 'dirname' keys, but .keys and .perl don't

The .gist output is bizarre. There should never be duplicate keys in a
Match. I haven't dived into the source code to see how that is even
possible.

From @pmichaud

On Thu, Apr 04, 2013 at 02​:09​:36PM -0700, Carl Mäsak wrote​:

<p6eval> rakudo 99e27f​: OUTPUT«｢/foo/bar/baz/｣␤ dirname =>
｢/foo/bar/baz/｣␤ dirname => ｢/foo/bar/｣␤ basename => ｢baz｣␤␤»
<labster> okay, why do I get two copies of dirname when the match only
succeeds once?
<masak> huuhhnn.
<masak> wut.
<masak> I suspect a backtracking-related glitch.
...
The .gist output is bizarre. There should never be duplicate keys in a
Match.

The "gist" method uses ".caps" for the match output, so I suspect
the culprit is in "caps", or in Match.gist's incorrect usage of .caps .

Duplicate keys can appear in the .caps stream.

Pm

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

From @usev6

There is no longer a duplicate key in the .gist output​:

$ perl6-m -e "say ('/foo/bar/baz/' ~~ m/^ $&lt;dirname&gt;=(.* '/'+)? $&lt;basename>=(<-[\/]>+) '/'* $ /).gist"
｢/foo/bar/baz/｣
dirname => ｢/foo/bar/｣
basename => ｢baz｣

I added a test to S02-names-vars/list_array_perl.t (couldn't find a better place) with the following commit​: Raku/roast@9acc51a8d9

Please note​: All of the above is under the assumption that the originial command (which is missing from the IRC log) was​:

r​: say ('/foo/bar/baz/' ~~ m/^ $&lt;dirname&gt;=(.* '/'+)? $&lt;basename>=(<-[\/]>+) '/'* $ /).gist

If I misinterpreted the problem, please reopen the ticket.

@usev6 - Status changed from 'open' to 'resolved'