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Re: [Caml-list] Weird typing problem
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Date: -- (:)
From: Ryan Tarpine <rtarpine@h...>
Subject: Re: [Caml-list] Weird typing problem
>From: Ching-Tsun Chou To: pixel@mandrakesoft.com CC: 
>caml-list@pauillac.inria.fr Subject: Re: [Caml-list] Weird typing problem 
>Date: Tue, 21 May 2002 16:20:11 -0700 (PDT)
>
>Thanks! But I still fail to see why the compiler and the interpreter should 
>behave differently.
>
>- Ching Tsun

Being only a beginner, I think it's because in the interpreter the type of 
the function doesn't need to be "finalized" completely, while in the 
compiler must *absolutely* have the exact type so it can generate code.  In 
the interpreter, it's fine for the type to be "refined" later on, because it 
won't be accessed by any outside applications.

The compiler can't generate code for functions with arguments of type '_a 
because that would require the object code to be modified when the function 
is called for the first time.  The code would need to be changed depending 
on which program called it, since (list_last [2;3]) and (list_last 
[2.0;3.0]) would have different effects (the first one would make the type 
of list_last be ints to ints while the second floats to floats).

HTH,

Ryan Tarpine, rtarpine@hotmail.com
"To err is human, to compute divine. Trust your computer but not its 
programmer."
- Morris Kingston

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