[perl #77006] cannot pass rule param to Grammar.parse method using => syntax

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# New Ticket Created by  Paweł Pabian 
# Please include the string:  [perl #77006]
# in the subject line of all future correspondence about this issue. 
# <URL: http://rt.perl.org/rt3/Ticket/Display.html?id=77006 >


This works fine:

[17:05] <bbkr> rakudo: grammar A {token t { ^\d\d$ }; }; say "OK" if 
A.parse("22", :rule<t>);
[17:05] <p6eval> rakudo 708347: OUTPUT«OK␤»

But this fails:
[17:05] <bbkr> rakudo: grammar A {token t { ^\d\d$ }; }; say "OK" if 
A.parse("22", rule => 't');
[17:05] <p6eval> rakudo 708347: OUTPUT«===SORRY!===␤Malformed regex at line 
22, near "=> 't');"␤»


[17:05] <bbkr> hmm, why the second case do not work? bug?
[17:06] <moritz_> parsing bug, probably
[17:06] <moritz_> it commits to parse it as a rule declarator