How would I construct a capture literal that has both an invocant and
at least one positional argument?  How do I distinguish this from a
capture literal that has no invocant and at least two positional

Gut instinct: if the first parameter in a list is delimited from the
rest using a colon instead of a comma, treat it as the invocant;
otherwise, treat it as the first positional argument.

This would mean that the rules for capturing are as follows:

* Capturing something in scalar context: If it is a pair, it is
captured as a named argument; otherwise, it is captured as the

* Capturing something in list context: Pairs are captured as named
arguments; the first non-pair is captured as the invocant if it is
followed by a colon, but as a positional argument otherwise; all other
non-pairs are captured as positional arguments.


 $x = /$a;      # $$x eqv $a
 $x = /:foo;    # %$x eqv { foo => 1 }
 $x = /($a,);   # @$x eqv ( $a ); is the comma neccessary, or are the
() enough?
 $x = /($a:);   # $$x eqv $a
 $x = /(:foo);  # %$x eqv { foo => 1 }; assuming that adverbs can go
inside ().
 $x = /($a, $b)      # @$x eqv ($a, $b)
 $x = /($a: $b)      # $$x eqv $a; @$x eqv ($b)
 $x = /:foo ($a: $b, $c):bar<baz> <== $d, $e <== flag => 0; # results
on next three lines:
   # $$x eqv $a
   # @$x eqv ($b, $c, $d, $e)
   # %$x eqv { foo => 1, bar => 'baz', flag => 0 }

Note that this approach makes it impossible for a pair to end up
anywhere other than as a named argument in the capture object; while
this makes sense when the capture object is being used as a proxy
argument list, it makes less sense when it is being used as the
equivalent of perl 5's references, and thus is probably a bug.

Jonathan "Dataweaver" Lang

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