doc: /* Move point N characters forward (backward if N is negative).
On reaching end or beginning of buffer, stop and signal error.
Interactively, N is the numeric prefix argument.
+If N is omitted or nil, move point 1 character forward.
Depending on the bidirectional context, the movement may be to the
right or to the left on the screen. This is in contrast with
doc: /* Move point N characters backward (forward if N is negative).
On attempt to pass beginning or end of buffer, stop and signal error.
Interactively, N is the numeric prefix argument.
+If N is omitted or nil, move point 1 character backward.
Depending on the bidirectional context, the movement may be to the
right or to the left on the screen. This is in contrast with