[perl #123470] LTA error on my $a vs $^a

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# New Ticket Created by  Elizabeth Mattijsen 
# Please include the string:  [perl #123470]
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# <URL: https://rt.perl.org/Ticket/Display.html?id=123470 >


[13:39:33]  <lizmat>    m: my $a; sub a { $a = $^b }; a 42   # works
[13:39:33]  <+camelia>  rakudo-moar 713600: ( no output )
[13:39:43]  <lizmat>    m: my $a; sub a { $a = $^a }; a 42   # does not work
[13:39:44]  <+camelia>  rakudo-moar 713600: OUTPUT«Cannot assign to an 
immutable value␤  in block <unit> at /tmp/DCMAx3q212:1␤␤»
[13:40:06]  <lizmat>    I guess $a and $^a take the same lexpad spot
[13:40:30]  <lizmat>    and the $^a this masks the outer $a
[13:40:36]  <lizmat>    *thus
[13:40:45]  <lizmat>    still, an LTA error
[13:41:12]  <lizmat>    rakudobuggable?  or DIHWIDT ?
[13:41:38]  <FROGGS_>   std: my $a; sub a { $a = $^a }; a 42
[13:41:39]  <+camelia>  std 76ccee1: OUTPUT«===SORRY!===␤$a 
has already been used as a non-placeholder in the surrounding sub block,␤  so 
you will confuse the reader if you suddenly declare $^a here at /tmp/yAB7rEr43U 
line 1:␤------> my $a; sub a { $a = ⏏$^a }; a 42…»
[13:42:15]  <FROGGS_>   I was about to say something like that :o)
[13:43:28]  <vendethiel>        std++
[13:44:14]  <FROGGS_>   ohh yeah, TimToady++
[13:44:42]  <FROGGS_>   std is a very awesome piece of work, every layer of it
[13:44:46]  <psch>      "you will confuse the reader" - that's pretty great
[13:45:09]  <psch>      "i as a computer don't have any problem with this, but 
you poor humans will scratch your head, so don't do that" :D
[13:45:15]  <isBEKaml>  yeah, that reads like "DIHWIDT"
[13:51:25]  <psch>      TimToady++ for cute SORRIES
[13:51:37]  <lizmat>    ok, so rakudobuggable since not std compliant