extents and insert-before-markers

Julian Bradfield writes: No. Neither extents nor their endpoints are markers, and markers are not extents. Extent behavior with respect to swallowing text inserted at an endpoint of the extent is entirely determined by the start-open and end-open properties of the extent. Markers do not have such properties, so the only way to get different behavior (ie, inserting text at a marker pushes the marker toward the end of the file instead of toward the beginning) is by changing the function call, which is why `insert-before-markers' exists. There are clearly applications where it makes sense for extent and marker behavior to be distinct in this respect (eg, in font-locking you don't want to have to fiddle with the openness or closedness of an extent depending on the kind of insertion you're doing). Do you have an application where you'd like it to work the other way around? Or is it incompatible with That Other Emacs? As for why this isn't documented, it is documented.<wink/> The documentation of `insert-before-markers' doesn't mention extents, so `insert-before-markers' should be assumed to have the same behavior as `insert' with respect to extents. I suppose we could add an explicit caveat to the docstring, though, as it's not necessarily intuitive that extent and marker behavior are not linked to each other. _______________________________________________ XEmacs-Beta mailing list XEmacs-Beta(a)xemacs.org http://lists.xemacs.org/mailman/listinfo/xemacs-beta