This looks cool and I wish I had time to play with it.
> On Aug 24, 2016, at 11:09 AM, Dupéron Georges <[email protected]> > wrote: > > Based on Asumu's work on type expanders > (https://github.com/racket/racket/compare/master...takikawa:tr-type-expander), > I have written a library which adds support for type expanders in > typed/racket. Type expanders are to types what match expanders are to match > patterns. A type expander is a special macro which can appear wherever a type > would normally be expected, and must expand to a type. > > The library is written using literate programming, with (a variant of) > scribble/lp2. The annotated source code is available here: > http://docs.racket-lang.org/type-expander.hl/ > and the documentation here: > http://docs.racket-lang.org/type-expander/ > > This library comes along with the multi-id library > (http://docs.racket-lang.org/multi-id/, literate source: > http://docs.racket-lang.org/multi-id.hl/), which allows easy definition of an > identifier which acts as a type expander, match expander, normal macro and > identifier macro. It can be used to define new datatypes, where a single > identifier represents the type, match clause, literal > instance as in (foo-datatype 1 2 3), and constructor function as in (map > foo-datatype …). > > The type-expander library is in beta status: > * It works well and I have been using it for a while without issues. > * The API should not change significantly in the future. > * However, there are many typed/racket primitives which are not > overloaded yet, as noted in the documentation (patches are welcome). > * Also, a couple of features are missing (patches are welcome again): > * The special form `Let`, which acts like `let-syntax` for types, > is only partially implemented. > * The special form `(Λ (stx) . body)`, which acts as an anonymous > type expander, is not implemented at all. > * There is no syntax-local-type-introduce. > > Any feedback is appreciated! :) > > Regards, > Georges Dupéron > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
