Hello. I am stuck on a probably simple type problem and was wondering if someone could help:
I'll just give the actual functions im using: ``` (struct Character ([bytes16 : Bytes])) (define substr (make-bytes 128)) (: make-character (-> Integer Integer Character)) (define (make-character s e) (Character (subbytes substr (* 2 s) (* 2 e)))) ``` What i want is a function like: ``` (: blah (-> (List Integer Integer) Character)) (define blah (λ (rng) (apply make-character rng))) ``` Which works. But note i can't just type (λ (rng) (apply make-character rng)) into the REPL, because i get: ; readline-input:5:14: Type Checker: Bad arguments to function in `apply': ; Domain: Integer Integer ; Arguments: Any ; in: (apply make-character rng) I think because i need the explicit (List Integer Integer) annotation to unify with (Listof Integer) Anyway, i wanted to make my code simpler so i was wondering if i could curry and partially apply. So i was digging around in the reference and tried: ``` (: blah2 (-> (List Integer Integer) Character)) (define2 blah2 ((curry (inst apply Integer Character)) make-character) ``` But i get: ; readline-input:8:40: Type Checker: type mismatch ; expected: (-> Integer * Character) ; given: (-> Integer Integer Character) ; in: make-character Looking at the typed racket reference and the type of apply, thought the star meant i could have many integers. Actually to be honest the discussion in typed racket reference "1.6 - Other Type Constructors" left me hanging a little bit on the function types, I am a pretty green on working with racket types and types in general. I thought this would unify but i guess i am completely wrong. Does anyone know what i am doing wrong exactly or what a very abbreviated form for what i want (behavior of blah) is? Sorry if this is basic i am a little lost on it as you can probably tell. Thank you Nate -- 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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/racket-users/CAM-xLPquALj6fqfxMhBuq402AAd4CNUCnxx2BvY0sQ2L4QOwog%40mail.gmail.com.
