numericValue for (unicode) characters

[H. S. Teoh]

On Wed, Jan 02, 2013 at 11:15:31PM +0100, monarch_dodra wrote:
> On Wednesday, 2 January 2013 at 20:49:38 UTC, Dmitry Olshansky
> wrote:
> >
> >Yup, and it's 2 lines then. And if one really wants to chain it:
> >map(a => enforce(std.ascii.isNumeric(a)), a -= '0')(...);
> >
> >Hardly makes it Phobos candidate then ;)
> 
> Well, just because its almost trivial to us doesn't mean it hurts to
> have it. The fact that you can even operate on chars in such a
> fashion (c - '0') is not obvious to everyone: I've seen time and
> time again code such as:
> //----
> if (97 <= c && c <= 122)
>     c -= 97;
> //----
> 
> numericValue helps keep things clean and self documented.

+1. Code intent is important.


[...]
> On Wednesday, 2 January 2013 at 20:13:32 UTC, Dmitry Olshansky
> wrote:
> >1/2/2013 7:24 PM, bearophile пишет:
> >>There is also std.typecons.nullable, it's a possibility for
> >>std.uni.numericValue. Generally Phobos should eat more of its
> >>dog food :-)
> >>
> >
> >double.nan sounds more like it.
> 
> Hum... nan. I like it.

+1 for nan. It's about time we used nan for something useful beyond just
an annoying default value for floating-point variables. :)


T

-- 
People say I'm indecisive, but I'm not sure about that. -- YHL, CONLANG