std.regex character consumption

[petevik38 at yahoo.com.au]

I've been running into a few problems with regular expressions in D. One
of the issues I've had recently is matching strings with non ascii
characters. As an example:

    auto re = regex( `(.*)\.txt`, "i" );
    re.printProgram();
    auto m = match( "bà.txt", re );
    writefln( "'%s'", m.captures[1] );

When I run this I get the following error:

dchar decode(in char[], ref size_t): Invalid UTF-8 sequence [160 46 116
120] around index 0
printProgram()
  0: 	REparen len=1 n=0, pc=>10
  9: 	REanystar
 10: 	REistring x4, '.txt'
 19: 	REend

While investigating the cause, I noticed that during execution of many
of the regex instructions (e.g. REanystar), the source is advanced with:

                src++;

However in other cases (REanychar), it is advanced with:

                src += std.utf.stride(input, src);

I found that by replacing the code REanystar with stride, the code
worked as expected. Although I can't claim to have a solid understanding
of the code, it seems to me that most of the cases of src++ should be
using stride instead.

Is this correct, or have I made some silly mistake and got completely
the wrong end of the stick?