Hi,

This question really applies for all Unicode encodings (UTF-8, UTF-16 and UTF-32). In the modern world you simply can't use indexed access into Object Pascal strings to retrieve a "character" (loosely what you see on the screen - ignoring combining diacritics). In my own projects I have custom written Iterators for various data types like StringList, ObjectLists etc, and that includes strings.

I know FPC RTL supports the Iterator concept (not as advanced as what I have implemented), but still useful. As far as I know there are some standard iterator classes already implemented. Does FPC include such iterators for the various string types?

Regards,
Graeme

Simply said: No. The character iterator

var
  C : Char;
  S : String; // or unicode string
begin
   for c in S do
end.

Will iterate bytes or words, not characters.

Michael.

Michael Van Canneyt wrote

Simply said: No. The character iterator Will iterate bytes or words, not characters.

OK thanks. So I definitely need the IsSurrogatePair() like function then
- in the case of UTF-16 encoded (UnicodeString) text. Do you know if such a function exists in the RTL? If not, I'll browse unicode.org to see what is required for such an implementation.

Regards,
Graeme

AFAIR, a member of the German Lazarus Forum implemented an iterator class for UTF8 some years ago (before there was Unicode support in fpc).

-Michael