On Fri, 27 Jun 2014 15:49:14 -0400 Sam Tobin-Hochstadt <sa...@cs.indiana.edu> wrote:
> On Fri, Jun 27, 2014 at 3:32 PM, Manfred Lotz > <manfred.l...@arcor.de> wrote: > > > > Argument 3: > > Expected: (-> b) > > Given: False > > > This is the key part of the error message: you have to provide a > function as the third argument, and you provided `#f`. I'd just change > that to (lambda () #f). > > Sam Ok, I did this but still not enough. test.rkt:10:14: Type Checker: Polymorphic function `hash-ref!' could not be applied to arguments: Argument 1: Expected: (HashTable a b) Given: (HashTable Nonnegative-Integer (Listof String)) Argument 2: Expected: a Given: Nonnegative-Integer Argument 3: Expected: (-> b) Given: (-> False) in: (hash-ref! my-hash size (lambda () #f)) context...: /home/manfred/racket/share/pkgs/typed-racket-lib/typed-racket/typecheck/tc-toplevel.rkt:249:0: type-check /home/manfred/racket/share/pkgs/typed-racket-lib/typed-racket/tc-setup.rkt:40:0: tc-setup /home/manfred/racket/share/pkgs/typed-racket-lib/typed-racket/typed-racket.rkt:25:4 standard-module-name-resolver Thanks, Manfred ____________________ Racket Users list: http://lists.racket-lang.org/users
