Re: [Caml-list] OCaml's variables

[oliver <oliver@first.in-berlin.de>]

On Sat, May 25, 2013 at 01:49:46PM +0200, Gabriel Scherer wrote:
> The name "variable" has been used for centuries by the mathematicians
> to denote exactly names that refer to values (of course immutable
> values, we're talking about mathematical objects her). There is no
> point in trying to change it because some people conflate this notion
> with mutability.
[...]

Yes, after rethinking this, this seems valid to me.
Even in a function that has only one solution, the
variables are called "variables".

I had in mind: if there is only one fixed solution,
it is not variable, hence it can't be called a variable.

With
  f(x) = 3 * x + 2
"x" is the variable.

f(x) can be calculated out of the function and the valaue of x.
Infinit many results, because infinite many x-values => variable.

But for f(x) = 0, which means
  0 = 3 * x + 2
the "x" also is called a variable, even though there is only one solution.

(...and "one solution" means: fixed result, not variable; but the term "variable"
 will be used nevertheless.

So, you are right.

I just was on the wrong track.
Temporarily black out ;-)


[...]
> The name "variable" is also used in the expression "type variable",
> which denotes for example the 'a in
>   val id : 'a -> 'a
> and which is clearly not associated to any form of mutation.

I wonder why I never had a problem with "type variable" but was
very picky about the term variable at the mentioned refman-page.
But I think it was influenced by the situation of the above
mentioned problem: "if it has only one fixed value it is not varible, it's fixed".
But as also explained above, the "x" nevertheless is called variable.

So my mouring about the reference manual at that point was rubbish.


Ciao,
   Oliver

P.S.: Thanks for the patience/calmness of you and the others.