Today's programming challenge - How's your Range-Fu ?

[Tobias Pankrath via Digitalmars-d]

> Wait, I thought the recommended approach is to normalize first, 
> then do
> string processing later? Normalizing first will eliminate
> inconsistencies of this sort, and allow string-processing code 
> to use a
> uniform approach to handling the string. I don't think it's a 
> good idea
> to manually deal with composed/decomposed issues within every 
> individual
> string function.


1. Problem: Normalization is not closed under almost all 
operations. E.g. concatenating two normalized strings does not 
guarantee the result is in normalized form.

2. Problem: Some unicode algorithms e.g. string comparison 
require a normalization step. It doesn't matter which form you 
use, but you have to pick one.

Now we could say that all strings passed to phobos have to be 
normalized as (say) NFC and that phobos function thus skip the 
normalization.