[perl #131853] [LTA] Error when missing `~~` in where clause: This type (QAST::WVal) does not support positional operations

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# New Ticket Created by  Zoffix Znet 
# Please include the string:  [perl #131853]
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# <URL: https://rt.perl.org/Ticket/Display.html?id=131853 >


17:55   Zoffix  m: subset Fun of Callable where .signature :(Int --> Int); say 
sub {} ~~ Fun
17:55   camelia rakudo-moar 46ef1b: OUTPUT: «===SORRY!===?This type 
(QAST::WVal) does not support positional operations?»

Missing `~~` between .signature and :(Int ...