bug#22313: 24.3; on global-font-lock-mode's documentation

[Eli Zaretskii]

> From: dbastos@toledo.com
> Date: Tue, 05 Jan 2016 15:39:36 -0200
> 
> I ran emacs -Q and so font-lock-mode came up enabled.  Good.  I then ran
> 
>   (global-font-lock-mode nil)
> 
> and it did turn off.  Looking at the documentation, I read the passage
> below.  It makes me think that the argument of nil, since that's not
> positive, would disable font-lock-mode, but it doesn't.  The function
> really needs a negative argument.  The documentation should be fixed.

Sorry, I don't understand which part of the documentation needs
fixing.  Can you clarify?

This part:

> If called from Lisp, enable the mode if ARG is omitted or nil.

clearly says that calling the function with nil as its argument
_enables_ the mode, not disables it.

As for being not positive, nil is not a number, so its sign is really
undefined, I think.