Re: [Caml-list] Newbie comment on constructor syntax

[Francois Berenger <francois.berenger@inria.fr>]

On 11/06/2015 10:33 AM, Soegtrop, Michael wrote:
> Dear Ocaml users,
>
> I just started to develop in OCaml, and must say it is smoother than expected. Although I did C/C++ for decades, I do less errors in Ocaml, both syntactically and in terms of if programs behave as expected. It appears to be much closer to human thinking than C/C++ and I already wonder how I could live without currying and type inference before.
>
> The one thing I find rather non intuitive is that variant constructors can take only one argument - or a tuple. Although I know it is wrong, I always write "Constr a b" instead of "Constr (a, b)". I know syntax is only a minor thing and mostly a matter of taste, but a large fraction of my syntax errors in new code are of this kind (when modifying code it is a bit different). Somehow I think this doesn't go together well with the function call syntax of OCaml. I guess deep in my brain a constructor is a function which takes arguments and returns an element of the type it constructs, so I guess I want to use the usual function call syntax.
>
> My question: Is there some syntax to give a constructor more than one argument which escaped me? Something like if I leave away the * in the definition I can use usual function call syntax in constructions and expressions? I would find this easier to read and to write, especially in matches or nested constructs. Does everybody use camlp4/p5/ppx to customize the syntax to his liking (as chapter 5 of the camlp4 manual suggests)? Or are there some long term advantages of this syntax I don't see as yet?

A dummy suggestion, but maybe you will like it:

let constr a b = Constr (a, b)

> Best regards,
>
> Michael
>
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-- 
Regards,
Francois.
"When in doubt, use more types"