Re: [Caml-list] use of ";;" when teaching Ocaml

[Daniil Baturin <daniil@baturin.org>]

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Hi Alan,

Since it's never necessary in the source code, I think it's a bad
practice to use it. Also, since it's uncommon in real-life code, I think
it will only cause more confusion in a long run.

Besides, top level pattern matching adds more safety and expressivity. From

let () = some_func x y z

it's clear that some_func is called solely for its side effects, and the
compiler will throw a type error if expression "some_func x y z" doesn't
have type unit.

Also, I rarely type the ;; after every phrase in the REPL, I like the
ability to type or paste longer chunks of code and process them at once.

On 06/22/2015 07:31 PM, Alan Schmitt wrote:
> Hello,
>
> In my Ocaml class, I tend to promote the use of ";;" to separate phrases
> (I'm basically following
>
http://ocaml.org/learn/tutorials/structure_of_ocaml_programs.html#Usingandomittingand
> although I was not aware of this page when I created the course). My
> motivation is to minimize the difference between using the top-level and
> writing files.
>
> I am now wondering if this is a good practice. In a nutshell, would you
> rather use
>
> #+begin_src ocaml
> let x = 12;;
> print_endline "Hello World!"
> #+end_src
>
> or
>
> #+begin_src ocaml
> let x = 12
> let () = print_endline "Hello World!"
> #+end_src
>
> when teaching Ocaml?
>
> Thanks,
>
> Alan
>


- -- 
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