Re: Hl-line and visual-line

[David Reitter <david.reitter@gmail.com>]

On May 23, 2010, at 4:33 PM, Eli Zaretskii wrote:
> 
>> The second use case would be to actually capture a whole line.  I have functions that kill the whole line (from left to right).   They would use `kill-region' from X to Y.   The same goes for hl-line-mode, where ONE overlay is drawn.
>> So, these functions would need a new function such as "regions-within-visual-line" or so, returning a list of (from . to) regions, or some other means of identifying the region. 
> 
> Sorry, I don't get this part.  Can you give an example that uses
> kill-region and another one with one overlay for hl-line-mode, and
> explain how the list of the form you mention would help?

Back to your example, buffer text is "abcde ABCDE FGHIJ xyz", displayed with word-wrap as

0) abcde JIHGF
1) EDCBA xyz

Say, point is in line 0, at "c".   Deleting the visual line should delete line 0, which is two portions of text: "abcde" and "FGHIJ".  
My reference to C-k assumed visual-line-mode semantics, as well, so C-k would delete "de" and "FGHIJ".


> Users expect logical-order regions.  Logical-order regions may surprise
> the first time you see it, but are easy to get used to, since that's
> the order you read the text you mark.

Yes, that sounds good.  I was just thinking about how marking a region by mouse would work; I have seen this with bidirectional text in a NS/Cocoa text edit view, and it seems reasonable.  You're probably in a much better position to tell what bidi users would expect.

D