transpose-subr

transpose-subr is a compiled Lisp function in `simple.el'.

(transpose-subr MOVER ARG &optional SPECIAL)

Subroutine to do the work of transposing objects.
Works for lines, sentences, paragraphs, etc. MOVER is a function that
moves forward by units of the given object (e.g. forward-sentence,
forward-paragraph). If ARG is zero, exchanges the current object
with the one containing mark. If ARG is an integer, moves the
current object past ARG following (if ARG is positive) or
preceding (if ARG is negative) objects, leaving point after the
current object.