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[Caml-list] Evaluation Order
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Date: 2001-06-10 (10:40)
From: Joerg Czeranski <jc@j...>
Subject: Re: [Caml-list] Evaluation Order
David McClain wrote:
> My mistake was writing
> let ans = process_stream() + process_tail()
> [...]
> The results of these two operations, integers, are arithmetically commutable
> under addition. But what isn't commutable is the order in which these
> operations occur. No current type checking in OCaml (or any other language
> with which I am familiar) could help catch this mistake.

A minor nit: commutativity isn't involved.
The problem would be the same for

  let y = f() / g()

and even

  let y = h (f()) (g())

Operators (and functions) just don't care in which order their operands
(parameters) are evaluated.

I really like Haskell's solution, but I've never used Haskell much.
The main reasons for this is OCaml's superior Unix binding
and it being much easier to build and install.

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