On Wed, Aug 15, 2018 at 9:22 AM, Matthias Felleisen <matth...@felleisen.org> wrote:
> > Also, do take a look at struct/c. > I don't think it covers the same need. It creates a contract that will review a struct after it has been created and identify whether or not it is well-formed, but it will not prevent you from creating a non-well-formed struct in the first place. Also, it obviously doesn't offer the other features of struct++. Keyword ctor, contracts, default values, field wrappers, and supertypes are working. Next step: shamelessly stea...er, take inspiration from lexi-lambda's work on struct-update so that I can make functional setters. (The only real difference I want is to set more specific contracts on the arguments to the setter instead of the any/c that struct-update uses.) > > > On Aug 15, 2018, at 1:31 AM, gfb <g...@cs.toronto.edu> wrote: > > > > You're losing the binding information by doing syntax->datum. Here's a > quick change to get you unstuck: > > > > ... > > (only-in racket/list partition flatten > append-map))) ; Include append-map > > ... > > (partition (syntax-parser [(flag _) (syntax-e #'flag)]) > > (syntax->list #'(item ...)))]) > > (define flat-mand (append-map (syntax-parser [(_ (kw contr)) > (list #'kw #'contr)]) > > mandatory)) > > (define flat-opt (append-map (syntax-parser [(_ (kw contr)) > (list #'kw #'contr)]) > > optional)) > > ... > > > > > > -- > > 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. > > 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 racket-users+unsubscr...@googlegroups.com. > 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 racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
