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Date: Mon, 17 Sep 2007 21:45:35 +0200
From: Fabrice Marchant <fabrice.marchant@orange.fr>
To: caml-list@yquem.inria.fr
Subject: Re: [Caml-list] Having '<<', why to use '|>' ?
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X-Spam: no; 0.00; pipelines:01 unix:01 avoids:01 caml-list:01 parentheses:01 functional:02 seems:03 tend:03 parameters:03 let:03 let:03 shell:04 passing:05 style:93 arguments:07 

> I think it's just a matter of style.  Your |> operator lets you write
> "pipelines" similar to the Unix shell, in which evaluation flows
> from left to right.  I've typically used this when I'm applying the
> function to all its arguments.  I tend to use the traditional
> composition operator (your <<), when I'm combining and passing
> functional values around.

  Thanks a lot !

So I will not add the use of "|>" to my habits. Simply using "<<" will help to keep things simple.

Only two or three operators seems very useful to me :

This one avoids some parentheses and let the code clear.
let ( @ ) f x = f x

The composition operator :
let ( << ) f g x = f @ g x

This one, written like this, is not a true operator, but is very useful to adapt parameters order :
let flip f x y = f y x

This other one, like "|>", doesn't appear to be essential :
let ( >> ) f g = ( << ) g f
( Can't write : let ( >> ) = flip ( << ) instead... )

Please are they other useful operators ?

Regards,

Fabrice