On 5/31/2014 10:06 PM, Philippe Verdy wrote:
I've not proposed to move these characters elsewhere (or ro reencode them), why do you think that?.

I just challenge your statement that a block cannot be discontinuous,

Well, go ahead and challenge that.

As implemented in the current nameslist and file blocks.txt a block would have this definition. "A block is a uniquely named, continuous, non-overlapping range of code points, containing a multiple of 16 code points, and starting at a location that is a multiple of 16."

Per chapter 3 the definition of the property block is given in Section 17.1 (Code Charts) - which contains no actual definition, only tells you how they are used in organizing the code charts, so, effectively, a block is what blocks.txt (and therefore the names list) say it is. The way blocks are assigned, has been following the empirically derived definition I gave above, and at this point, the production process for the code charts has some of these restrictions built in.

Chapter 3 calls blocks an enumerated property, meaning that the names must be unique, and blocks.txt associates a single range with a name, in concurrence with the glossary, which says blocks represent a range of characters (not a collection of ranges). Likewise, changing blocks to not starting at or containing multiples of 16 code points (sometimes called a "column") is equally not in the cards - it would break the very production process for chart production. The description of how blocks are used does not contemplate that they can be mutually overlapping, so that becomes part of their implicit definition as well.

There's reason behind the madness of not providing an explicit definition of "block" in the standard. It has to do with discouraging people from relying on what is largely an editorial device (headers on charts). However, it does not mean that arbitrary redefinition of a block from a single to multiple ranges is something that can or should be contemplated.

So, the chances that UTC would agree to such changes, even if not formally guaranteed, is de facto nil.

A./

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