[perl #119133] method signature does not parse: couldn't find final ')' WAT?

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# New Ticket Created by  Elizabeth Mattijsen 
# Please include the string:  [perl #119133]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org:443/rt3/Ticket/Display.html?id=119133 >


[00:50:00] <lizmat>      r: multi method a( %t, *@l ) { foo( -> $v { %t{$v} }, 
*@l ) }  # WAT? am I doing wrong here ?
[00:50:01] <+camelia>    rakudo 1b5924: 
OUTPUT«===SORRY!===␤Unable to parse expression in argument 
list; couldn't find final ')'␤at /tmp/EslBeuK3ls:1␤------>  a( %t, *@l ) { 
foo( -> $v { %t{$v} }, *⏏@l ) }  # WAT? am I doing wrong here ?␤  
  expecting any of:␤        postfix…
[00:53:54] <arcterus>    lizmat: are you trying to do this?
[00:54:29] <arcterus>    multi method a(%t, *@l) { foo( -> $v, *@l { %t{$v} } ) 
}
[00:56:02] <lizmat>      no, the sub should only be called with the one 
parameter
[00:56:11] <lizmat>      by the subroutine
[00:56:43] <lizmat>      the rest of the parameters are the values on which the 
sub should work
[00:58:42] <arcterus>    what about this
[00:59:14] <arcterus>    multi method a(%t, *@l) { foo( -> $v { %t{$v} }, |@l) }
[01:00:11] <lizmat>      r: multi method a(%t, *@l) { foo( -> $v { %t{$v} }, 
|@l) }
[01:00:13] <+camelia>    rakudo 1b5924: OUTPUT«Useless declaration of a 
has-scoped multi-method in mainline␤===SORRY!===␤Undeclared 
routine:␤    foo used at line 1␤␤»
[01:01:15] <lizmat>      I'll try it nonetheless in the actual situation after 
the running spectest is done
[01:01:48] <arcterus>    k
[01:09:29] <lizmat>     arcterus: that compiles
[01:10:01] <lizmat>      testing...
[01:10:03] <arcterus>    cool.
[01:11:02] <lizmat>      but tests fail
[01:11:20] <lizmat>      :-(
[01:13:03] <lizmat>      giving up for today: it was just a code optimization 
anyway...
[01:13:33] lizmat        submits rakudobug