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Date: Fri, 20 Jan 2012 22:04:30 +0100
From: oliver <oliver@first.in-berlin.de>
To: Edgar Friendly <thelema314@gmail.com>
Cc: caml-list@inria.fr
Message-ID: <20120120210430.GA2188@siouxsie>
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Subject: Re: [Caml-list] is there a more concise way to write this?


My fold approach version:

let folded (out, value) o v =
  let a = if out   then Some o else None in
  let b = if value then Some v else None in
  List.fold_left ( fun accum elem -> match elem with None -> accum | Some x -> x :: accum ) [] [ b; a ]

or when following the way the other functions are notated
(o and v not as parameters but in the environment) so that
you can paste it into your code:


let folded_env (out, value) =
  let a = if out   then Some o else None in
  let b = if value then Some v else None in
  List.fold_left ( fun accum elem -> match elem with None -> accum | Some x -> x :: accum ) [] [ b; a ]

If
  let ... = ... in  let ... = ...  in ...
is slower than than 
  let ... = ... and let ... = ...  in ...

then use the latter one ;-)


Ciao,
   Oliver