About std.ascii.toLower

[bearophile]

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