On 4/20/2014 6:54 PM, James Clark wrote:
On Mon, Apr 21, 2014 at 2:58 AM, Asmus Freytag <[email protected]
<mailto:[email protected]>> wrote:
On 4/20/2014 3:24 AM, Eli Zaretskii wrote:
Would someone please help understand the following subtleties and
obscure language in the UBA document found at
http://www.unicode.org/reports/tr9/? Thanks in advance.
3. Paragraph 3.3.2 says, under "Non-formatting characters":
X6. For all types besides B, BN, RLE, LRE, RLO, LRO, PDF, RLI, LRI,
FSI, and PDI:
. Set the current character’s embedding level to the embedding
level of the last entry on the directional status stack.
[...]
Note that the current embedding level is not changed by this rule.
What does this last sentence mean by "the current embedding level"?
The first bullet of X6 mandates that "the current character’s
embedding level" _is_ changed by this rule, so what other "current
embedding level" is alluded to here?
I'm punting on that one - can someone else answer this?
I assume "current embedding level" here meant "the embedding level of
the last entry on the directional status stack". (This is a natural
slip to make if you think in terms of an optimized implementation that
stores each component of the top of the directional status stack in a
variable, as suggested in 3.3.2.)
James
In general, I heartily dislike "specifications" that just narrate a
particular implementation...
A./
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