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Date: Wed, 19 Nov 2003 20:54:08 -0700
To: caml-list@inria.fr
From: Peter Scott <sketerpot@chase3000.com>
Subject: [Caml-list] Recursive apply function
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I'm having an interesting disagreement with ocaml about types. I'm trying 
to make a function to imitate the lisp apply function. That is, I want to 
make a function which will apply another function to a list.

I came up with this code:

let rec apply f args =
   match args with
       arg :: rest -> apply (f arg) rest
     | [] -> f;;

let add x y = x + y;;
let x = apply add [2; 3];;
print_int x;;

As you can see, the idea is to go recursively applying the function to the 
first element of the list. Unfortunately, I get this message when run: 
"This expression has type 'a but is here used with type 'b -> 'a", 
referring to the "(f arg)" part.

Is there a way around this?

-Peter

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