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Date: -- (:)
From: Jacques Garrigue <garrigue@k...>
Subject: Re: [Caml-list] Frustrated Beginner
From: Brian Hurt <bhurt@spnz.org>

> > Mmm, not really convinced. For me ;, is a shortcut for :
> > 
> >   let () = ... in
> 
> Or more accurately
> 	let _ = ... in ...

Well, both wrong :-)
The error/warning behaviour differs.

Actually, there are 4 possibilities:

construct  \  type    unit      'a       function       other
let () = ... in ...   OK        OK(*)    error          error
let _ = ... in ...    OK        OK       OK             OK
ignore (...); ...     OK        OK       warning        OK
...; ...              OK        OK       warning        warning

(*) the result type is unified with unit.

So, you have plenty of choice on how to sequence your code.
Additionally there are compiler options to ignore warnings or turn
them into errors.
(Having been bitten several times, I actually suggest avoiding "let _"
as it discards the very useful partial application warning. But of
course your need it for side-effecting code returning a function.)

     Jacques

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