> (One of the design goals of Perl 6 was to become good at this.
> Perl 6 has been vaporware for ~15 years now.)

Actually Perl 6 Grammars have been very good for 5 years now -- it was necessary to do this part first, because Perl 6 is parsed with Perl 6. Mainly because nothing else is good enough to parse Perl 6 syntax with any level of sanity. One can throw together a little DSL pretty easily: write up a grammar that looks not too different from a spec, add a few actions to the AST, and call a parse file method.

As to the vaporware part, the release date for 6.0.0 is Christmas 2015, with a fixed spec and a compiler that meets that spec. Which is not to say that it's not ready for some purposes now. Grammars, in particular, are a very mature feature. Native arrays... somewhat less so.

That said about the release timing, I should try to fix some Perl 6 compiler bugs this weekend.