Adding more content from OP (seems there's some possible delay/issue with RT emails) per https://irclog.perlgeek.de/perl6/2017-08-29#i_15086833
---------------------------------------------------------------------------------------- This is Rakudo version 2017.07-155-gc229022cb built on MoarVM version 2017.07-378-g5e94da03 implementing Perl 6.c. Linux Kataomoi 4.13.0-rc6 CPU E3-1230 V2 @ 3.30GHz GenuineIntel GNU/Linux Also tested on IRC with Moar and Star This is not specific to right side nested alternations. Example 4: 'succeed'.match(/ [fail || succeed] | suc /).say; Result: ｢suc｣ Expected: ｢succeed｣
