[perl #131089] Different parsing of combined colonpairs

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# New Ticket Created by  Zoffix Znet 
# Please include the string:  [perl #131089]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=131089 >


If joined colonpairs are after a position arg, only the first colonpair gets 
registered:

    <Zoffix__> m: -> *@_, *%_ { dd [@_, %_] }("/", :r:w:d:x)
    <camelia> rakudo-moar 1b9d53: OUTPUT: «[["/"], {:r}]␤»

But if they're first in line, then all do:

    <Zoffix__> m: -> *@_, *%_ { dd [@_, %_] }(:r:w:d:x, "/")
    <camelia> rakudo-moar 1b9d53: OUTPUT: «[["/"], {:d, :r, :w, :x}]␤»

When in a [], only first one is obtained as well:
    <Zoffix__> m: dd [:r:w:d:x]
    <camelia> rakudo-moar 1b9d53: OUTPUT: «[:r]␤»

And when in a {}, all are obtained, but only the first one gets value True 
(related?)
    <Zoffix__> m: dd {:r:w:d:x}
    <camelia> rakudo-moar 1b9d53: OUTPUT: «Hash % = {:d(1), :r, :w(1), :x(1)}␤»