[perl #117417] Colon in sub or method definition causes QAST::Op invoke() error

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# New Ticket Created by  Brent Laabs 
# Please include the string:  [perl #117417]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org:443/rt3/Ticket/Display.html?id=117417 >


labster: r: sub foo ($bar :D) { 1; }
[8:51pm] p6eval: rakudo 897636: OUTPUT«===SORRY!===␤invoke() not
implemented in class 'QAST::Op'␤»
[8:54pm] labster: I guess I want Mu:D there.  But definitely LTA error
message.
[8:55pm] sorear: rakudobug. internal error.
[8:57pm] labster: r: sub x ($y :qwerty) { 3; }
[8:57pm] p6eval: rakudo 897636: OUTPUT«===SORRY!===␤invoke() not
implemented in class 'QAST::Op'␤»
[8:58pm] labster: r: sub x ($y qwerty) { 3; }
[8:58pm] p6eval: rakudo 897636: OUTPUT«[31m===[0mSORRY![31m===[0m␤Missing
block␤at /tmp/gHtxH4GsMT:1␤------> [32msub x ($y [33m⏏[31mqwerty) { 3;
}[0m␤    expecting any of:␤        statement list␤        prefix or
term␤        prefix or meta-prefix␤        new name to be defined␤
formal pa…
[8:58pm] labster: looks like the colon triggers it.