[perl #74430] [BUG] Indexing and 'is copy' array parameters interact badly in Rakudo

[Carl Mäsak]

# New Ticket Created by  "Carl Mäsak" 
# Please include the string:  [perl #74430]
# in the subject line of all future correspondence about this issue. 
# <URL: http://rt.perl.org/rt3/Ticket/Display.html?id=74430 >


<colomon> rakudo: my @a = 1..10; say @a.PARROT; @a.splice(0, 1); say @a
<p6eval> rakudo 78faa0: OUTPUT«Array␤2345678910␤»
<colomon> rakudo: my @a = 'a'..'g'; say @a.PARROT; @a.splice(0,1); say @a;
<p6eval> rakudo 78faa0: OUTPUT«Array␤bcdefg␤»
<colomon> rakudo: sub foo(@items is copy) { @items.splice(0, 1); say
@items; }; my
          @items = 'a'..'g'; foo(@items);
<p6eval> rakudo 78faa0: OUTPUT«No applicable candidates found to
dispatch to for 'postcircumfix:<[ ]>'. Available candidates are:␤:(Mu
: Int $i;; *%_)␤:(Mu : Block $b;; *%_)␤:(Mu :
!whatever_dispatch_helper ;; *%_) [...]
<colomon> bingo
<colomon> bug?
<jnthn> huh, wtf.
<jnthn> Yes, I think bug.
<jnthn> is copy fail maybe?
<pmichaud> that'd be my guess.
<colomon> is copy fail of some sort, it seems.
<jnthn> Weird.
<colomon> rakudo: sub foo(@items is copy) { say @items[0..^1]; say
@items; }; my @items = 'a'..'g'; foo(@items); say @items;
<p6eval> rakudo 78faa0: OUTPUT«No applicable candidates found to
dispatch to for 'postcircumfix:<[ ]>'. Available candidates are:␤:(Mu
: Int $i;; *%_)␤:(Mu : Block $b;; *%_)␤:(Mu :
!whatever_dispatch_helper ;; *%_) [...]
<colomon> There you go.
<masak> rakudobug?
<colomon> masak: totally.
* masak submits
<pmichaud> rakudo: sub foo(@items is copy) { say PARROT(@items); };
my @items = 'a'..'g';  foo(@items);
<p6eval> rakudo 78faa0: OUTPUT«ObjectRef->Array␤»
<pmichaud> that "ObjectRef->Array" seems suspect.
<jnthn> yeah, moze byt
<jnthn> Perhaps a binder tweak is needed.