<div dir="ltr">We cannot get rid of procedure-arity-includes?, but we could make it accept either a procedure or an arity for both arguments.<div> </div><div style>For the second bullet, I think that we'd run afoul of backwards compatibility problems. That is, there is code out there that currently builds and works with arities that are not normalized and we'd break it if we required all arity-accepting primitives to be given normalized arities.</div> <div style> </div><div style>But maybe that's warranted?</div><div style> Robby</div></div><div class="gmail_extra"> <div class="gmail_quote">On Thu, Apr 11, 2013 at 10:33 AM, Eli Barzilay <<a href="mailto:eli@barzilay.org" target="_blank">eli@barzilay.org</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">OK, that's a valid use case -- but isn't it better for both of these uses to just use some combinator for arities that generates a properly normalized arity instead of constructing lists and explicitly normalizing them? It's just that the interface looks very complex now. Some obvious things: * `procedure-arity-includes?' vs `arity-includes?' (but it's the second that compares two procedures... I'd just make the first accept a procedure to avoid this unfortunate naming.) * `normalize-arity', `normalized-arity?', `arity=?' (go away with a combinator, the last one gets replaced with `equal?') <div class="HOEnZb"><div class="h5"> A few minutes ago, Carl Eastlund wrote: > If we want people to be able to create higher-order functions with > precise arities via procedure-reduce-arity, for instance, we need to > provide tools for manipulating arity values. Manipulating them is > also useful for producing error messages that describe the arity of > procedure values. I don't see any reason to close this stuff off, > when it's the one useful, non-opaque aspect of procedure values. > > Carl Eastlund > > On Thu, Apr 11, 2013 at 11:13 AM, Eli Barzilay <<a href="mailto:eli@barzilay.org">eli@barzilay.org</a>> wrote: > > Is there a real need to make this whole thing a public interface? I'd > think that a general direction is to move away from making it public > (ie, remove the ability to create an arity value), and this seems to > add a pretty big chunk of stuff in the opposite direction. > > About two weeks ago, <a href="mailto:cce@racket-lang.org">cce@racket-lang.org</a> wrote: > > cce has updated `master' from 6e40caa7e2 to df00bbb194. > > <a href="http://git.racket-lang.org/plt/6e40caa7e2..df00bbb194" target="_blank">http://git.racket-lang.org/plt/6e40caa7e2..df00bbb194</a> > > > > =====[ 7 Commits ]====================================================== > > Directory summary: > > 21.0% collects/racket/private/ > > 21.5% collects/racket/ > > 26.4% collects/scribblings/reference/ > > 30.9% collects/tests/racket/ > > > > ~~~~~~~~~~ > > > > 59b1e32 Carl Eastlund <<a href="mailto:cce@racket-lang.org">cce@racket-lang.org</a>> 2013-03-30 11:45 > > : > > | Changed normalize-arity to coalesce arity-at-least with adjacent > numbers. > > | > > | For instance, (normalize-arity (list 1 (arity-at-least 2))) now > produces > > | (arity-at-least 1). The implementation and the tests for > normalize-arity both > > | reflect this change. The randomized tests now also check that the > output > > | represents the same arity as the input. > > : > > M collects/racket/private/norm-arity.rkt | 82 +++++++++++++--------- > > M collects/tests/racket/basic.rktl | 112 > +++++++++++++++++++++++++----- > > > > ~~~~~~~~~~ > > > > e356c66 Carl Eastlund <<a href="mailto:cce@racket-lang.org">cce@racket-lang.org</a>> 2013-03-30 11:49 > > : > > | Re-provide normalize-arity from racket/function. > > : > > M collects/racket/function.rkt | 4 ++-- > > > > ~~~~~~~~~~ > > > > 4dd011a Carl Eastlund <<a href="mailto:cce@racket-lang.org">cce@racket-lang.org</a>> 2013-03-30 15:49 > > : > > | Added documentation for normalize-arity. > > : > > M collects/scribblings/reference/procedures.scrbl | 42 > ++++++++++++++++++---- > > > > ~~~~~~~~~~ > > > > 636f8a9 Carl Eastlund <<a href="mailto:cce@racket-lang.org">cce@racket-lang.org</a>> 2013-03-30 21:04 > > : > > | Moved normalized-arity?, arity=?, and arity-includes? into racket/ > function. > > : > > M collects/racket/function.rkt | 94 > +++++++++++++++++++++++++++++++++++- > > M collects/tests/racket/basic.rktl | 96 > +------------------------------------ > > > > ~~~~~~~~~~ > > > > aaa99d5 Carl Eastlund <<a href="mailto:cce@racket-lang.org">cce@racket-lang.org</a>> 2013-03-30 21:05 > > : > > | Documented normalized-arity?, arity=?, and arity-includes?. > > : > > M collects/scribblings/reference/procedures.scrbl | 87 > +++++++++++++++++++--- > > > > ~~~~~~~~~~ > > > > f509420 Carl Eastlund <<a href="mailto:cce@racket-lang.org">cce@racket-lang.org</a>> 2013-03-30 17:12 > > : > > | Removed unnecessary duplication of normalize-arity. > > : > > M collects/tests/racket/fixnum.rktl | 21 ++------------------- > > > > ~~~~~~~~~~ > > > > df00bbb Carl Eastlund <<a href="mailto:cce@racket-lang.org">cce@racket-lang.org</a>> 2013-03-31 10:34 > > : > > | Updated contracts for arity-related functions. > > | > > | Added contract checking to arity=?, arity-includes?, and > normalized-arity. > > | Removed contract checking from normalize-arity to make it a total > predicate. > > | Updated documentation for normalize-arity to reflect this change. > > : > > M collects/racket/function.rkt | 21 > ++++++++++++++++----- > > M collects/racket/private/norm-arity.rkt | 2 ++ > > M collects/scribblings/reference/procedures.scrbl | 13 ++++++------- > > -- > ((lambda (x) (x x)) (lambda (x) (x x))) Eli Barzilay: > <a href="http://barzilay.org/" target="_blank">http://barzilay.org/</a> Maze is Life! > -- ((lambda (x) (x x)) (lambda (x) (x x))) Eli Barzilay: <a href="http://barzilay.org/" target="_blank">http://barzilay.org/</a> Maze is Life! </div></div><div class="HOEnZb"><div class="h5">_________________________ Racket Developers list: <a href="http://lists.racket-lang.org/dev" target="_blank">http://lists.racket-lang.org/dev</a> </div></div></blockquote></div> </div>