It is not easy to display a value of point in the middle of a
sequence of text that has the
is invisible. Therefore, after a command finishes and returns to the
command loop, if point is within such a sequence, the command loop
normally moves point to the edge of the sequence.
A command can inhibit this feature by setting the variable
If this variable is non-
nilwhen a command returns to the command loop, then the command loop does not check for those text properties, and does not move point out of sequences that have them.
The command loop sets this variable to
nilbefore each command, so if a command sets it, the effect applies only to that command.