I think concrete means well-defined in this context.

Isn't it also a way to specify an interface only?

Both Perl 6 and Moose allow that, yes.

Perl 6 - the future is here, just unevenly distributed

In reply to Re: what means concrete in perlglossary/role - a concrete set of behaviors? by moritz
in thread what means concrete in perlglossary/role - a concrete set of behaviors? by Anonymous Monk

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