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partial instantiation of a new obj. : bug or feature ?
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Date: -- (:)
From: Christian Boos <boos@a...>
Subject: partial instantiation of a new obj. : bug or feature ?

Hi, 

It seems that partial instantiation of objects' new statement didn't work 
as I expected.
I thought that the creation of an object takes place when all the arguments
are available.

The following example illustrates this:

  # class test (a : int) (b : int) =
       val a = a
       val b = b
       method get = (a, b)
    end;;
  class test (int) (int) = val a : int val b : int method get : int * int end
  # let a1 = new test 1;;
  val a1 : int -> test = <fun>
  # let b1 = a1 1;;
  val b1 : test = <obj>
  # let b2 = a1 2;;
  val b2 : test = <obj>
  # b1 = b2;;
  - : bool = true
  # b1#get;;
  - : int * int = 1, 2
  # b2#get;;
  - : int * int = 1, 2
  # 

This forces one to write things like :

  let objs = Array.map (fun i -> new test 1 i) vals

instead of the more intuitive :

  let objs = Array.map (new test 1) vals


Maybe someone wants to comment ?

-- Christian