Toggle subword movement and editing (Subword mode).
With a prefix argument ARG, enable Subword mode if ARG is
positive, and disable it otherwise. If called from Lisp, enable
the mode if ARG is omitted or nil.
Subword mode is a buffer-local minor mode. Enabling it remaps
word-based editing commands to subword-based commands that handle
symbols with mixed uppercase and lowercase letters,
e.g. "GtkWidget", "EmacsFrameClass", "NSGraphicsContext".
Here we call these mixed case symbols `nomenclatures'. Each
capitalized (or completely uppercase) part of a nomenclature is
called a `subword'. Here are some examples:
Nomenclature Subwords
===========================================================
GtkWindow => "Gtk" and "Window"
EmacsFrameClass => "Emacs", "Frame" and "Class"
NSGraphicsContext => "NS", "Graphics" and "Context"
The subword oriented commands activated in this minor mode recognize
subwords in a nomenclature to move between subwords and to edit them
as words.
Uses keymap `subword-mode-map', which is not currently defined.
(fn &optional ARG)