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RE: [Caml-list] eval order and 'and'
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Date: -- (:)
From: Sven LUTHER <luther@d...>
Subject: Re: [Caml-list] eval order and 'and'
On Wed, Sep 11, 2002 at 01:05:46AM -0400, Arturo Borquez wrote:
> Chris Hecker <checker@d6.com> wrote:
> 
> >
> >Does "let a and b in" guarantee a is evaluated before b, like "let a in let 
> >b in" does?
> >
> Sorry but I don't understand the purpose of your question.
> If a and b are functions with 'related side effects' the secure
> way should be the later ('let a in let b ..'), otherwise
> the order of evaluation in the first case is irrelevant
> as a and b are two unrelated functions (with no side effects),
> or 'let a and b in ..' is the same as 'let b and a in ..' 

So he can do things like :

if x <> 0 and 1 / x ... 

like it is possible to do in C, instead of doing :

if x <> 0 then if 1 / x ...

which gives more lines of code, and needs to redefine two time the else
condition.

Anyway, i don't think the order is defined, but in any case, i guess
it would be revere sequential if anything (execution starts from the
right).

But then again, it could be different in bytecode and in native code.

Friendly,

Sven Luther
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