[perl #128262] [LTA ERROR] Using Junction or `where` in --> (returns) part of signature

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# New Ticket Created by  Zoffix Znet 
# Please include the string:  [perl #128262]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=128262 >


<Zoffix> m: sub foo (--> Str|Int)  {  }; foo
<camelia> rakudo-moar 1ab1fb: OUTPUT«===SORRY!=== Error while compiling 
/tmp/Pkq21Gs0mf␤Type 'Str' is not declared. Did you mean 'str'?␤at 
/tmp/Pkq21Gs0mf:1␤------> sub foo (--> Str⏏|Int)  {  }; foo␤»
<Zoffix> m: sub (--> Str|Int)  { }()
<camelia> rakudo-moar 1ab1fb: OUTPUT«===SORRY!=== Error while compiling 
/tmp/HHZJP38YXq␤Type 'Str' is not declared. Did you mean 'str'?␤at 
/tmp/HHZJP38YXq:1␤------> sub (--> Str⏏|Int)  { }()␤»
<Zoffix> m: sub (--> Int|Str)  { }()
<camelia> rakudo-moar 1ab1fb: OUTPUT«===SORRY!=== Error while compiling 
/tmp/dHpYCgJ8pg␤Type 'Int' is not declared. Did you mean 'int'?␤at 
/tmp/dHpYCgJ8pg:1␤------> sub (--> Int⏏|Str)  { }()␤»
<Zoffix> m: sub (--> Any where Int|Str)  { }()