[perl #113546] Duplicate flattened nameds aren't filtered out

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# New Ticket Created by  Kristof Bogaerts 
# Please include the string:  [perl #113546]
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# <URL: https://rt.perl.org:443/rt3/Ticket/Display.html?id=113546 >


p6: sub s_s(*%n)  { %n>>.say }; s_s(|{:assoc<list>}, :assoc<left>); #
which one is correct?
rakudo e75a0a: OUTPUT«duplicate named argument in call␤  in block
<anon> at /tmp/ohG08nWXj0:1␤␤»
niecza v18-6-ge52d6c3: OUTPUT«left␤» 21:54:05

p6: sub s_s(*%n)  { %n>>.say }; s_s(:assoc<list>, :assoc<left>);        
rakudo e75a0a, niecza v18-6-ge52d6c3: OUTPUT«left␤»

jnthn:
Rakudo has inconsistent behavior in that areas.
For non-flattened nameds it filters out the dupes
Flattened ones it can't do that, and Parrot barfs on dupe named args.