[perl #126606] [BUG] Can't call .WHICH on Iteratable or Iterator due to accidental punning

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# New Ticket Created by  Larry Wall 
# Please include the string:  [perl #126606]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=126606 >


21:25 < TimToady> m: say Iterable === Any
21:25 <+camelia> rakudo-moar 2ad739: OUTPUT«Method 'iterator' must be
implemented by Iterable because it is required by a role␤  in any
                 compose_method_table at gen/moar/m-Metamodel.nqp:2661␤  in
any apply at gen/moar/m-Metamodel.nqp:2671␤  in any compose at
                 gen/moar/m-Metamodel.nqp:2807␤  in…»
21:49 < TimToady> m: sub foo(Iterable $s) {...}; say &foo.signature
21:49 <+camelia> rakudo-moar 2ad739: OUTPUT«Method 'iterator' must be
implemented by Iterable because it is required by a role␤  in any
                 compose_method_table at gen/moar/m-Metamodel.nqp:2661␤  in
any apply at gen/moar/m-Metamodel.nqp:2671␤  in any compose at
                 gen/moar/m-Metamodel.nqp:2807␤  in…»
21:50 < TimToady> that tries to call Iterable.WHICH, and that forces role
punning, which doesn't work here
21:50 < TimToady> m: say Iterable.foo
21:50 <+camelia> rakudo-moar 2ad739: OUTPUT«Method 'iterator' must be
implemented by Iterable because it is required by a role␤  in any
                 compose_method_table at gen/moar/m-Metamodel.nqp:2661␤  in
any apply at gen/moar/m-Metamodel.nqp:2671␤  in any compose at
                 gen/moar/m-Metamodel.nqp:2807␤  in…»
21:50 < TimToady> doesn't matter which method you call on it