Character Range: surrogate blocks

Richard Emberson emberson at
Sun Oct 18 00:20:18 BST 1998

To extend the available characters in Unicode one
can use to 16 bit characters with surrogate blocks.

Now in production rule #2 titled Character Range 
surrogate blocks are explicitly excluded (along 
with FFFF and FFFE). 

Does that mean that if one were reading a character
stream that included characters not in the basic 
set of Unicode characters (those not using surrogate
blocks) that it would be a wellformedness violation?

There are the extra, beyond 16-bit, characters specified
by the spec in production rule #2 as "[x10000-#x10FFFF]".
Is this how Unicode characters that use the surrogate
blocks get represented in an XML document? Is there
an algorithm for the convertions defined somewhere? 

Short of getting a copy of the Unicode 2.0 spec, is there 
anywhere where the conversion algorithm is documented?

Why was it decided to exclude the uses of surrogate 
block-base Unicode characters within XML documents?



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