[perl #119929] multi sub with/out named parameters, which selected?

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# New Ticket Created by  Elizabeth Mattijsen 
# Please include the string:  [perl #119929]
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# <URL: https://rt.perl.org:443/rt3/Ticket/Display.html?id=119929 >


[13:18:06] <lizmat>      r: multi sub a ($a) { say "without named" }; multi sub 
a ($a, :$foo) { say "with named" }; a("bar")   # bug or feature ??
[13:18:07] <+camelia>    rakudo c5ba78: OUTPUT«with named␤»
[13:18:25] <lizmat>      given 2 candidates, one without named, and one with an 
optional named
[13:18:42] <colomon>     lizmat: how could that not be a bug?
[13:18:51] <lizmat>      is it right that the candidate with the optional named 
parameter is selected even if there is no named parameter given ?
[13:19:14] <masak>       lizmat: I think in this case, it comes down to 
ordering.
[13:19:22] <masak>       lizmat: I'd need to re-read S06 to be sure.
[13:19:36] <masak>       lizmat: but if it comes down to ordering, I still 
think the first one should win.
[13:20:15] <lizmat>      r: multi sub a ($a, :$foo) { say "with named" }; multi 
sub a ($a) { say "without named" }; a("bar")   # which one wins ?
[13:20:16] <+camelia>    rakudo c5ba78: OUTPUT«with named␤»
[13:20:32] <lizmat>      seems to not be an order thing here
[13:21:02] <lizmat>      seems the candidate without named params is always 
ignored (to me, at least)
[13:23:12] <lizmat>     colomon: how could that not not be a bug ?
[13:24:13] <FROGGS>      n: multi sub a ($a, :$foo) { say "with named $a $foo" 
}; multi sub a ($a) { say "without named $a" }; a("bar")   # checking niecza
[13:24:15] <+camelia>    niecza v24-95-ga6d4c5f: OUTPUT«without named bar␤»
[13:24:43] <lizmat>      rn: multi sub a ($a, :$foo) { say "with named $a $foo" 
}; multi sub a ($a) { say "without named $a" }; a("bar")
[13:24:48] <+camelia>    rakudo c5ba78: OUTPUT«use of uninitialized value of 
type Any in string context  in sub a at /tmp/8jPolJRUuH:1␤␤with named bar ␤»
[13:24:48] <+camelia>    ..niecza v24-95-ga6d4c5f: OUTPUT«without named bar␤»
[13:25:06] <lizmat>      I think this calls for either a rakudo or niecza bug
[13:25:07] <colomon>     lizmat: I would (possibly naively) expect the most 
specific multi to win.  but the least specific multi is winning.  my default 
assumption is bug.
[13:25:18] <FROGGS>      lizmat: I think it should complain about an ambigious 
all
[13:25:21] <FROGGS>      call*
[13:25:25] <lizmat>      that at least
[13:25:47] <lizmat>      but how can "no named parameters" not be narrower than 
"any named parameters" ?
[13:25:51] <colomon>     seems like we've thought up three possible behaviors, 
and rakudo is doing *none* of them.
[13:26:17] lizmat        submits rakudobug