Thanks for the question, I've tried to clarify it.

I think "idfirst" meant "a character that is allowed as the first character of an identifier", and the authoritative source in all parsing questions says that's <.alpha> (Unicode category "Letter", or the underscore).

Perl 6 - second systems done right

In reply to Re: Perl6: What is "idfirst letter"? by moritz
in thread Perl6: What is "idfirst letter"? by rir

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