About std.ascii.toLower

[monarch_dodra]

On Thursday, 20 September 2012 at 17:05:18 UTC, bearophile wrote:
> monarch_dodra:
>
>> Would that actually change anything though? I mean what with 
>> alignment and everything, wouldn't returning a char be just as 
>> expansive? I'm not 100% sure.
>
> If you are thinking about the number of operations, then it's 
> the same, as both a char and dchar value go in a register. The 
> run time is the same, especially after inlining.
>
>
>> What is your use case that would require this?
>
> I have a char[] like:
>
> ['a','x','b','a','c','x','f']
>
> Every char encodes something. Putting it to upper case means 
> that that data was already used:
>
> ['a','X','b','a','C','x','f']
>
> In this case to use toUpper I have to use:
>
> cast(char)toUpper(foo[1])
>
> What's I am trying to minimize is the number of cast(). On the 
> other hand even in C toupper returns a type larger than char:
>
> http://www.acm.uiuc.edu/webmonkeys/book/c_guide/2.2.html
>
> It's just D has contract programming, and this module is 
> written for ASCII, so it's able to be smarter than C functions, 
> and return a char.
>
> Bye,
> bearophile

That's what I thought. You have a valid point (IMO) but at the 
same time, using the ASCII methods on non-ascii characters is 
also legit operation.

I guess we'd need the extra "std.strictascii" module (!) for 
operations that would accept ASCII char, and return a ASCII char.

I'd support such an ER, I think it would. Allow users (such as 
you) to have tighter constraints if needed, while still keeping 
std.ascii for "safer" ASCII operations.