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 racket-users+unsubscr...@googlegroups.com. > 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 racket-users+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/racket-users/20201210164936.elqk6qsc76yhn4wc%40topoi.pooq.com.
