I think that's off topic, it's a type declaration and not an attribute.

Very different things, type declarations are just stubs and badly documented and I think nothing happened there in the last 20 years.

> "bound to the use of the fields pragma"

see fields

compile-time checking if you use hash keys of a typed Hash/Class.

also hardly used

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re^2: I don't like annotation syntax by LanX
in thread I don't like annotation syntax by Liebranca

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