std.string.join & co. do a character-by-character copy because hasLength!string is false

[Vladimir Panteleev]

On Fri, 27 May 2011 21:18:40 +0300, Jonathan M Davis <jmdavisProg at gmx.com>  
wrote:

> On 2011-05-27 11:05, Vladimir Panteleev wrote:
>> Why hasLength!string is false:
>> https://github.com/D-Programming-Language/phobos/blob/96941d5384a5fee302df/
>> std/range.d#L767
>>
>> Would it make sense to introduce a hasOpaqueLength oslt. to fix this?
>
> Um. Why? What would it give you? hasLength is intended for range-based  
> stuff.
> and and any arrays of char or wchar are ranges of dchar, so they don't  
> have a
> length property as far as ranges are concerned. If you want your  
> template to
> work with any of the string types, then just use isSomeString to check  
> whether
> it's a string. What would hasOpaqueLength do? What would it get you?  
> Yes, the
> situation with char and wchar technically having a length property but  
> having
> hasLength be false for them is a bit odd, but it works, and hasLength  
> does
> exactly what it's supposed to - check whether the type has a length  
> property
> for use with ranges. And char and wchar arrays don't.

Wow, you sure took your time to bash my stupid suggestion :) I agree  
completely, TBH I only added that because I didn't want my post to look  
like a complaint without even an attempt to suggest a solution.

As long as std.array.join & co. don't do a character-by-character copy for  
strings, I'm happy. Still, putting isSomeString in std.array/std.range  
checks seems like a hack to me.

-- 
Best regards,
  Vladimir                            mailto:vladimir at thecybershadow.net