[perl #64566] @a[1..*] adds trailing undef value

[Moritz Lenz via RT]

On Wed Apr 08 14:59:19 2009, moritz wrote:
> 23:55 <@moritz_> rakudo: my @a = 1..4; say @a[1..*].perl
> 23:56 < p6eval> rakudo 6b9755: OUTPUT«[2, 3, 4, undef]␤»
> 
> It should just be [2, 3, 4].

Since the discussion came up on #perl6 if this is really the expected
behaviour, S09 says:

As the end-point of a range, a lone "whatever" means "to the maximum
specified index" (if fixed indices were defined):

    say @calendar[5..*];          # Same as:  say @calendar[5..11]
    say @calendar{Jun..*};        # Same as:  say @calendar{Jun..Dec}

or "to the largest allocated index" (if there are no fixed indices):

    say @data[1..*];              # Same as:  say @results[1..5]


It doesn't mention how the postcifcumfix:<[ ]> is supposed to introspect
those to find out if the WhateverCode object constructed by 1..* needs
to receive self.elems or self.elems-1 as an argument.

Which is why I CC: p6l to get some ideas or clarification, and if we
want to maintain this DWIMmy but not very consistent behaviour.

Cheers,
Moritz