[perl #63800] Method 'result_object' not found calling make in a grammar action method

[Patrick R. Michaud via RT]

Rakudo now gives a much more useful error message for the case where
make() cannot set a result object:

    $ cat 63800
    grammar G {
        regex TOP { 'a' {*} }
    }

    class GA {
        method TOP($m) { make GA.new }
    }

    G.parse('a', :action(GA.new));

    $ ./perl6 63800
    make() cannot set result of non-Match object in $/
    in method GA::TOP (63800:6)
    called from regex G::TOP (63800:1)
    called from Main (63800:9)
    $ 

Closing ticket, thanks!

Pm