Converting a character to upper case in string

[Laurent Tréguier]

On Friday, 21 September 2018 at 13:32:54 UTC, NX wrote:
> On Friday, 21 September 2018 at 12:34:12 UTC, Laurent Tréguier 
> wrote:
>> I would probably go for std.utf.decode [1] to get the 
>> character and its length in code units, capitalize it, and 
>> concatenate the result with the rest of the string.
>>
>> [1] https://dlang.org/phobos/std_utf.html#.decode
>
> So by this I assume it is sufficient to work with dchars rather 
> than graphemes?

----------
import std.stdio;
import std.conv;
import std.string;
import std.uni;

size_t index = 1;
auto theString = "he\u0308llo, world";
auto theStringPart = theString[index .. $];
auto firstLetter = theStringPart.decodeGrapheme;
auto result = theString[0 .. index]
     ~ capitalize(firstLetter[].text)
     ~ theString[index + graphemeStride(theString, index) .. $];
writeln(result);
----------

This will capitalize graphemes as a whole, and might be better 
than what I previously wrote.