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From: Goswin von Brederlow <goswin-v-b@web.de>
To: Daniel Buenzli <daniel.buenzli@erratique.ch>
Cc: caml-list <caml-list@inria.fr>
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	Buenzli"'s message of "Thu, 7 Jun 2012 19:34:49 +0200")
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Subject: Re: [Caml-list] Local functions with arguments or closures ?

Daniel Bünzli <daniel.buenzli@erratique.ch> writes:

> Hello, 
>
> In the past I remember having indirectly benchmarked two different styles for writing local functions :
>
>     let f x = 
>       let v = ... in
>       let rec loop x v = ... in 
>       loop x v 
>
> or 
>
>     let f x = 
>         let v = ... in
>         let rec loop () = ... (* uses v and x *) in 
>         loop ()
>
> without being able to reach a conclusion. Is there any particular style that is definitively faster ? Does it maybe depend on the number of arguments and/or on whether loop is recursive or not ? 
>
> This question keeps coming back in my mind when I write local functions... I'm sure someone with some knowledge of the compiler's internals can provide a more reasonable answer than benchmarks.  
>
> Best,
>
> Daniel

Closure arguments prevent what little optimization there is in ocaml. So
better avoid them where time counts. But your example doesn't have any
closure arguments.

MfG
        Goswin