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From: Ching-Tsun Chou <ctchou@mipos2.intel.com>
To: caml-list@pauillac.inria.fr
Subject: [Caml-list] Weird typing problem
Date: Tue, 21 May 2002 15:13:45 -0700 (PDT)	[thread overview]
Message-ID: <200205212213.g4LMDjQ26439@zws707.sc.intel.com> (raw)


Consider a file "zzz.ml" that contains only two lines:

let (<<) f g x = f (g (x))
let list_last = List.hd << List.rev

Now, if I load the file interactively, I get:

<unix> ocaml
        Objective Caml version 3.04

# #use "zzz.ml" ;;
val ( << ) : ('a -> 'b) -> ('c -> 'a) -> 'c -> 'b = <fun>
val list_last : '_a list -> '_a = <fun>
# 

However, if I try to compile it, I get:

<unix> ocamlc -c zzz.ml
File "zzz.ml", line 2, characters 16-35:
The type of this expression, '_a list -> '_a,
contains type variables that cannot be generalized


Why so?

- Ching Tsun
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             reply	other threads:[~2002-05-21 22:13 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-05-21 22:13 Ching-Tsun Chou [this message]
2002-05-21 23:03 ` Pixel
2002-05-21 23:20   ` Ching-Tsun Chou
2002-05-21 23:48 Ryan Tarpine
     [not found] <F143h1mIs1Dk3fqSUVd000021b5@hotmail.com>
2002-05-21 23:58 ` Ching-Tsun Chou
2002-05-22  0:14 Ryan Tarpine

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