[perl #128702] Range in container coerced to Num inside array subscript

[jn...@jnthn.net via RT]

On Fri Jul 22 15:34:02 2016, gfldex wrote:
> my @numbers =  <4 8 15 16 23 42>; my $range = 0..2; .say for
> @numbers[$range];
> # OUTPUT«16␤»
> # expected:
> # OUTPUT«4␤8␤15␤»
> 
This is correct, and part of the "Scalar container implies item" rule. Changing 
it would break things like the second evaluation here:

> my @x = 1..10; my @y := 1..3; @x[@y]                    
(2 3 4)
> @x[item @y]
4

Noting that since a range can bind to @y in a signature, then Range being a 
special case would make an expression like @x[$(@arr-param)] unpredictable in 
its semantics.

> # also binding to $range provides the expected result
> my @numbers =  <4 8 15 16 23 42>; my $range := 0..2; .say for
> @numbers[$range];
> # OUTPUT«4␤8␤15␤»
> y

This is also expected, since with binding there is no Scalar container to 
enforce treatment as an item.

So, all here is working as designed.