This function can be used to transpose stretches of text:
function transpose-regions start1 end1 start2 end2 \&optional leave-markers
This function exchanges two nonoverlapping portions of the buffer (if they overlap, the function signals an error). Arguments
end1 specify the bounds of one portion and arguments
end2 specify the bounds of the other portion.
transpose-regions relocates markers with the transposed text; a marker previously positioned within one of the two transposed portions moves along with that portion, thus remaining between the same two characters in their new position. However, if
leave-markers is non-
transpose-regions does not do this—it leaves all markers unrelocated.