String Prefix Predicate

[monarch_dodra via Digitalmars-d-learn]

On Thursday, 14 August 2014 at 17:41:08 UTC, Nordlöw wrote:
> On Thursday, 14 August 2014 at 17:33:41 UTC, Justin Whear wrote:
>> std.algorithm.startsWith?  Should auto-decode, so it'll do a
>
> What about 
> https://github.com/D-Programming-Language/phobos/pull/2043
>
> Auto-decoding should be avoided when possible.
>
> I guess something like
>
> whole.byDchar().startsWith(part.byDchar())
>
> is preferred right?

I don't get it? If you use "byDchar", you are *explicitly* 
decoding. How is that any better? If anything, you are 
*preventing* the (many) opportunities phobos has to *avoid* 
decoding when it can...

If you really want to avoid decoding, use either "representation" 
which will do char[] => ubyte[] conversion, or "byCodeUnit", 
which will create a range that returns single elements (IMO, 
"byCodeUnit" should be prefered over "byChar", as it infers the 
correct width).