Yes I remember digging into it and the fields Pragma.

And ....

# this will generate a compile-time error
my Foo $foo = Foo->new;
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I could see a use case in extending this already existing syntax for other purposes, like

• allowing to translate a subset of Perl to inline C
• helping IDEs to intellisense method expansions
• defining an initial type (e.g. for serializers ; sic)

But probably I'm naive.