Re: [Texmacs-dev] Understanding cursor->delta

[David Allouche]

On Mon, May 24, 2004 at 03:37:12PM -0400, address@hidden wrote:

> According to the documentation, the delta in the cursor is only need
> to detect "environment changes".  I have been experimenting with it
> the following way:
> 
> I first removed, the delta member variable from cursor_rep and then
> recompiled TeXmacs.  Everywhere delta was used, I set it to 0.  All
> the compilation errors were fixed by removing any reference to
> cursor->delta.  Then I typed in TeXmacs:
> 
> Testing<with|font-series|bold|BOLD>attributes
> 
> When moving the cursor with my keyboard left and right, I did not find
> any difference whatsoever.
> 
> So why do we need it?  I was kind of hoping that I would see a
> difference in the way the cursor behaved across the boundary of the
> word "BOLD" in my testcase.

One thing where it makes a difference, is when you press down-arrow then
up-arrow. The delta is used to remember on what side of the environment
boundary the cursor should get.

-- 
                                                            -- ddaa