From @ronaldxs

According to the docs​:
http://docs.perl6.org/type/Grammar#method_parse
"Method parse ... Returns a Match object on success, and Nil on failure."

18​:07 mr_ron m​: grammar G { token TOP { a+ } }; my Nil $x = G.parse("zz")
18​:07 camelia rakudo-moar 273e89​: OUTPUT«Type check failed in assignment to $x; expected Nil but got Any␤ in block <unit> at /tmp/HMNfyPJjvI​:1␤␤»

17​:56 mr_ron m​: grammar G { token TOP { a+ | <bs> }; token bs { b+ } }; say G.parse("zz").WHAT; say G.parse("aa")<bs>.WHAT
17​:56 camelia rakudo-moar 273e89​: OUTPUT«(Any)␤Nil␤»

Then
http://irclog.perlgeek.de/perl6/2015-11-03#i_11477014

From @ronaldxs

According to the docs​:
http://docs.perl6.org/type/Grammar#method_parse
"Method parse ... Returns a Match object on success, and Nil on failure."

18​:07 mr_ron m​: grammar G { token TOP { a+ } }; my Nil $x = G.parse("zz")
18​:07 camelia rakudo-moar 273e89​: OUTPUT«Type check failed in assignment to $x; expected Nil but got Any␤ in block <unit> at /tmp/HMNfyPJjvI​:1␤␤»

17​:56 mr_ron m​: grammar G { token TOP { a+ | <bs> }; token bs { b+ } }; say G.parse("zz").WHAT; say G.parse("aa")<bs>.WHAT
17​:56 camelia rakudo-moar 273e89​: OUTPUT«(Any)␤Nil␤»

Then http://irclog.perlgeek.de/perl6/2015-11-03#i_11477014

From @ronaldxs

On Tue, 03 Nov 2015 14​:26​:06 -0800, ronaldxs wrote​:

18​:07 mr_ron m​: grammar G { token TOP { a+ } }; my Nil $x =
G.parse("zz")
18​:07 camelia rakudo-moar 273e89​: OUTPUT«Type check failed in
assignment to $x; expected Nil but got Any␤ in block <unit> at
/tmp/HMNfyPJjvI​:1␤␤»

17​:56 mr_ron m​: grammar G { token TOP { a+ | <bs> }; token bs { b+ }
}; say G.parse("zz").WHAT; say G.parse("aa")<bs>.WHAT
17​:56 camelia rakudo-moar 273e89​: OUTPUT«(Any)␤Nil␤»

Reran test cases and they now run as expected. Might be of interest to add test case(s?) to roast/S05-match/non-capturing.t?

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

From @AlexDaniel

Is this ticket relevant today?

Note that we also have this​: https://rt-archive.perl.org/perl6/Ticket/Display.html?id=131919
On 2016-12-19 08​:41​:33, ronaldxs wrote​:

On Tue, 03 Nov 2015 14​:26​:06 -0800, ronaldxs wrote​:

18​:07 mr_ron m​: grammar G { token TOP { a+ } }; my Nil $x =
G.parse("zz")
18​:07 camelia rakudo-moar 273e89​: OUTPUT«Type check failed in
assignment to $x; expected Nil but got Any␤ in block <unit> at
/tmp/HMNfyPJjvI​:1␤␤»

17​:56 mr_ron m​: grammar G { token TOP { a+ | <bs> }; token bs { b+ }
}; say G.parse("zz").WHAT; say G.parse("aa")<bs>.WHAT
17​:56 camelia rakudo-moar 273e89​: OUTPUT«(Any)␤Nil␤»

Reran test cases and they now run as expected. Might be of interest
to add test case(s?) to roast/S05-match/non-capturing.t?

From @ronaldxs

Hopefully it's just a doc issue but​:

https://docs.perl6.org/routine/parse

still says​:

Returns a Match object on success, and Nil on failure.

From @ronaldxs

Noticed that RT #​131919 is new and may apply to 6.d and would like to take a few days to review further.

From @ronaldxs

Request for test cases now roast issue​: Raku/roast#297

Planning to close this ticket soon if no objection.

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