Current behavior seems to be satisfactory now:
$ perl6 -e 'role R { has $.x }; role S does R { has $.x }; S.new;'
Attribute '$!x' conflicts in role composition
Test added in https://github.com/perl6/roast/commit/c65ed93912
closing.
The examples would fail usage constraints with the parameterless MAIN.
I could not get them to fail with any internal messages on current rakudo,
either with the parameterless MAIN or with a MAIN that had a :$y.
Haven't looked as to when this got fixed.
Tests added for both cases (though I had t
