On Wed, Dec 09, 2020 at 10:16:16PM -0800, unlimitedscolobb wrote: > On Wednesday, December 9, 2020 at 11:50:26 PM UTC+1 Ben Greenman wrote: > > > > If the answer is no, is there any interest in including these three > > > functions (as well as compose-5, 6, 7, 8) into Typed Racket? > > > > I think these would be excellent in a package. > > > > A package for compose-n and compose-3 to like 10 or 20? > > I'm still not sure about how high the granularity of packages may get in > Racket, but I'd like to share these functions, because they feel very > useful to me. > > > > Someday later, perhaps poly dots and #:rest-star can combine to > > improve the built-in type. > > > > >From my naive viewpoint, I don't really see other natural ways of improving > the type of compose other than what I wrote, the problem being that writing > the type for arbitrary-arity composition would require specifying equality > between the return type of every function and the argument type of the > preceding one. I'm not sure even Coq and Agda have that facility directly, > certainly not Haskell or Idris to the best of my knowledge. I don't expect > them to go beyond binary compose, because it's sufficient to do any > compositions. It's that in Racket I find writing chains of nested compose > calls somewhat clunky. > > I'm not sure whether macros could be of use here. I'll give it a think.
Idea: Have a look at parendown https://docs.racket-lang.org/parendown/index.html It would let you write (compose f (compose g (compose h k))) as ( compose f #/ compose g #/ compose h k ) Which at least cuts down on the heavy indentation and parenthesis pile-up. A macro might be able to generate either of the above from (comp f g h k) . -- hendrik > > - > Sergiu > > -- > 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]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/racket-users/d0eacc64-c11b-4edd-aa38-c62c15494c06n%40googlegroups.com. -- 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]. To view this discussion on the web visit https://groups.google.com/d/msgid/racket-users/20201210164936.elqk6qsc76yhn4wc%40topoi.pooq.com.
