From @lizmat

$ 6 'my Int @​a; @​a[5] = 42; $_ = 666 for @​a'
Cannot assign to an immutable value
  in block <unit> at -e​:1

[23​:11​:32] <lizmat> .tell jnthn my Int @​a; @​a[5] = 42; $_ = 666 for @​a fails because it gets an IterationBuffer as target, not an ArrayReificationTarget
[23​:12​:26] <lizmat> .tell the IterationBuffer doesn't have a descriptor

So I think it could be a code gen issue. And is my previous fix for​:

$ 6 'my Int @​a; @​a[5] = 42; .say for @​a'
(Int)
(Int)
(Int)
(Int)
(Int)
42

basically wrong, as we don’t have typed lists (and those (Int) are appearing there because I took the .of of the given list, which gives the right type, but no descriptor. In other words, for the @​a case, it should never wind up in the List iterator anyway?

Liz

From @smls

Confirmed on current Rakudo.

Interestingly, it works if `for @​a` is replaced with `for @​a[*]`​:

  ➜ my Int @​a; @​a[5] = 42; $_ = 100 for @​a[*]; say @​a;
  [100 100 100 100 100 100]

From @dogbert17

On Sat, 07 May 2016 13​:26​:09 -0700, smls75@​gmail.com wrote​:

Confirmed on current Rakudo.

Interestingly, it works if `for @​a` is replaced with `for @​a[*]`​:

➜  my Int @​a;  @​a\[5\] = 42;   $\_ = 100 for @​a\[\*\];  say @​a;
\[100 100 100 100 100 100\]

Seems to have been fixed with Rakudo commit 069b789af545dff30d450618fae82ccb82579346.
Tests needed.

The RT System itself - Status changed from 'new' to 'open'

From @AlexDaniel

Tests added in Raku/roast@d78f339

Closing

On 2018-02-06 14​:12​:56, jan-olof.hendig@​bredband.net wrote​:

On Sat, 07 May 2016 13​:26​:09 -0700, smls75@​gmail.com wrote​:

Confirmed on current Rakudo.

Interestingly, it works if `for @​a` is replaced with `for @​a[*]`​:

➜ my Int @​a; @​a[5] = 42; $_ = 100 for @​a[*]; say @​a;
[100 100 100 100 100 100]

Seems to have been fixed with Rakudo commit
069b789af545dff30d450618fae82ccb82579346.
Tests needed.

@AlexDaniel - Status changed from 'open' to 'resolved'