[perl #74946] %h.delete() in right side of expression causes left side key missing

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# New Ticket Created by  Paweł Pabian 
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perl6 -e 'my %h = {"a" => "b"}; %h{"a"} = %h.delete("a"); say %h.perl;'
{}

I'm not sure if it's a bug.

I expect right side to be evaluated and THEN assignment to performed.
So this assignment should behave as:
 %h{"a"} = "b"
And hash should not be empty.

bbkr