std.getopt suggestion

[Andrei Alexandrescu]

On 9/28/11 12:44 PM, Jonathan M Davis wrote:
> Okay. I have a suggestion for an improvement to std.getopt that I think merits
> a bit of discussion. There's currently a pull request with some improvements
> for getopt which are mostly internal changes rather than API changes (
> https://github.com/D-Programming-Language/phobos/pull/272 ), but I think that
> there is an API change that we should consider.
>
> Right now, there are three configuration options which are mutable module-level
> variables:
>
> dchar optionChar = '-';
> string endOfOptions = "--";
> dchar assignChar = '=';
>
> and the aforementioned pull request adds another for an array separator.
> Mutable module/global variables are generally considered to be bad design
> (though they're sometimes necessary), and I'm very much inclined to have those
> variables _not_ be at the module scope like that.

Why?

> So, my suggestion is that we create a GetOpt struct which contains all of the
> options for getopt, and we make getopt a member function of that struct.

If the only motivation is that "globals are bad" without further 
reasoning, I see this as keeping with the letter but not with the spirit 
of the law.


Andrei