Re: languages and PHP

At 11:09 AM +0100 10/2/07, Colin Guthrie wrote:

tedd wrote:

Isn't UTF-8 the big fish here? Sure there' UTF-16 and larger, but everything else is a subset of UTF-8, is it not? So, what's the problem if you get a character defined by ISO -- it's still within the UTF-8 super-group, right?

Individual characters are sometimes OK, but it's the sequence of characters that could be invalid. UTF-8 works by using special bits at the MSB end of the byte to say, "I can't represent this character in one byte, I need to use 2 bytes (or 3 bytes)" (and maybe also 4? can't remember of the top of my head). In a multi-byte sequence the MSB end of all the bytes must follow a pre-defined scheme. If they do not they are syntactically invalid UTF-8. So it's more than just individual characters, the order of them is important. Hope that explains it (although probably a bad explanation as I'm very tired right now!). Col

Ah, I see what you're saying. I've run into that before when studying Unicode. The mb_ series of functions deal with larger than ASCII coding, but I don't know of any that deals with character sequence/combinations or right/left readings. That's all Greek to me, pardon the pun. Cheers, tedd -- ------- http://sperling.com http://ancientstones.com http://earthstones.com