At Fri, 6 Jun 2014 13:23:15 -0400, Asumu Takikawa wrote: > On 2014-06-06 06:31:27 +0100, Matthew Flatt wrote: > > Sorry for being so late to the discussion, but I agree that something > > like `class-constructor-arity` and `class-constructor-arity-includes?` > > should be added to `racket/class`. > > Are those even possible to implement? > > After all, I can construct a class that has 2 init arguments on > Wednesday and has 3 on Friday (by checking the date and then using > different `super-new` calls in the branches).
Good point! The `make-object` function doesn't check arities or argument names in advance; it has to wait to see what a initialization expressions do. I think we could add a function that reports argument information for simple classes, where "simple" is based on the relevant class expressions conforming to syntactic constraints. The constraints would be a simplified (and documented) variant of the constraints that are currently used to determine whether use-before-definition checks are needed for accesses of a field's classes. Is argument information useful enough to do that? ____________________ Racket Users list: http://lists.racket-lang.org/users
