XEmacs text props

XEmacs text props

[Lars Magne Ingebrigtsen]

I have been unable to do anything sensible with the `start-closed'
text/extent property.  Whatever I do, I just can't seem to get those
pesky props to close.  I've tried `put-text-property' and
`map-extents'/`set-extent-propery' on all the extents, but they still
remain stubbornly open.  Which makes the topic display look kinda
yucky. 

I'm sure I'm doing something silly, since I seem to remember Ben
saying this should be working...

-- 
(domestic pets only, the antidote for overdose, milk.)
  larsi@ifi.uio.no * Lars Ingebrigtsen

Re: XEmacs text props

[Steven L Baur]

>>>>> "Lars" == Lars Magne Ingebrigtsen <larsi@ifi.uio.no> writes:

Lars> I have been unable to do anything sensible with the
Lars> `start-closed' text/extent property.  Whatever I do, I just
Lars> can't seem to get those pesky props to close.  I've tried
Lars> `put-text-property' and `map-extents'/`set-extent-propery' on
Lars> all the extents, but they still remain stubbornly open.  Which
Lars> makes the topic display look kinda yucky.

Lars> I'm sure I'm doing something silly, since I seem to remember Ben
Lars> saying this should be working...

He fixed the test case I posted which illustrated the original problem.

You want the end points open not closed.  The terminology here looks
very badly worded:

> Whether the extent overlaps its endpoints is governed by its
> `start-open' and `end-open' properties.  Insertion of a character at a
> closed endpoint will expand the extent to include that character;
> insertion at an open endpoint will not.  Similarly, functions such as
> `extent-at' that scan over all extents overlapping a particular
> position will include extents with a closed endpoint at that position,
> but not extents with an open endpoint.

What's wrong with doing something like:
(defun test-text-properties ()
  (interactive)
  (let ((beg (point)))
    (save-excursion
      (insert "This is a test.\n")
      (add-text-properties beg (point) (list 'start-open t
					     'face 'italic
					     'start-closed nil
					     'steve-property "Emacs Rules"))))
  (let ((beg (point)))
    (save-excursion
      (insert "This is some more text.\n")
      (add-text-properties beg (point) (list 'start-open t
					    'start-closed nil
					    'end-open t
					    'end-closed nil
					    'face 'bold)))))

In other words, brute force it.

The original test case (which doesn't work at all in 19.13) looked like:
(defun test-text-properties ()
  (interactive)
  (let ((beg (point)))
    (save-excursion
      (insert "This is a test.\n")
      (add-text-properties beg (point) (list 'start-open t
					     'face 'italic
					     'start-closed nil
					     'steve-property "Emacs Rules"))))
  (insert "This is some more text.\n"))

-- 
steve@miranova.com baur
Unsolicited commercial e-mail will be proofread for $250/hour.
Andrea Seastrand: For your vote on the Telecom bill, I will vote for anyone
except you in November.

Re: XEmacs text props

[Lars Magne Ingebrigtsen]

Steven L Baur <steve@miranova.com> writes:

> You want the end points open not closed.

Whee!  I changed `start-closed' to `start-open', and now everything
works!  

>  The terminology here looks
> very badly worded:
> 
> > Whether the extent overlaps its endpoints is governed by its
> > `start-open' and `end-open' properties.  Insertion of a character at a
> > closed endpoint will expand the extent to include that character;
> > insertion at an open endpoint will not.  Similarly, functions such as
> > `extent-at' that scan over all extents overlapping a particular
> > position will include extents with a closed endpoint at that position,
> > but not extents with an open endpoint.

Hm.  When a text property is open, insertion at end points will not
expand the prop.  Uhum.  Yup.  :-)

Well, anyways, now that I understand that I didn't understand the
terminology, we should have seen the end of those numerous text prop
bleeds that have plagued Gnus under XEmacs.

-- 
(domestic pets only, the antidote for overdose, milk.)
  larsi@ifi.uio.no * Lars Ingebrigtsen

Re: XEmacs text props

[Per Abrahamsen]

Think about ranges in math.  An open range does not include the
endpoints while a closed range does.  Open and closed extents in
XEmacs are similar, only the closed extents include the endpoints.

Re: XEmacs text props

[Lars Magne Ingebrigtsen]

Per Abrahamsen <abraham@dina.kvl.dk> writes:

> Think about ranges in math.  An open range does not include the
> endpoints while a closed range does.  Open and closed extents in
> XEmacs are similar, only the closed extents include the endpoints.

That makes sense, now that you mention it.

-- 
(domestic pets only, the antidote for overdose, milk.)
  larsi@ifi.uio.no * Lars Ingebrigtsen

Re: XEmacs text props

[Steven L Baur]

>>>>> "Lars" == Lars Magne Ingebrigtsen <larsi@ifi.uio.no> writes:

Lars> Well, anyways, now that I understand that I didn't understand the
Lars> terminology, we should have seen the end of those numerous text prop
Lars> bleeds that have plagued Gnus under XEmacs.

The properties still bleed in the *Summary* buffer when pseudo
articles are created by X u.  The *Group Topic* buffer has been
corrected, though.

-- 
steve@miranova.com baur
Unsolicited commercial e-mail will be proofread for $250/hour.
Andrea Seastrand: For your vote on the Telecom bill, I will vote for anyone
except you in November.