30.5 Marker Insertion Types

When you insert text directly at the place where a marker points, there are two possible ways to relocate that marker: it can point before the inserted text, or point after it. You can specify which one a given marker should do by setting its insertion type. Note that use of insert-before-markers ignores markers’ insertion types, always relocating a marker to point after the inserted text.

Function: set-marker-insertion-type marker type

This function sets the insertion type of marker marker to type. If type is t, marker will advance when text is inserted at its position. If type is nil, marker does not advance when text is inserted there.

Function: marker-insertion-type marker

This function reports the current insertion type of marker.

Most functions that create markers, without an argument allowing to specify the insertion type, create them with insertion type nil. Also, the mark has, by default, insertion type nil.