mouse-autoselect-window needs a delay

[Marshall, Simon]

This isn't a bug as such, but a suggestion for feature refinement.

I like the concept of mouse-autoselect-window, since it allows me to attempt to mimic my WM's focus-follows-mouse frame policy for Emacs windows.  But there's always a but.

If you have a split window but the invocation of a command forces you to move the mouse across a different window, you will probably end up applying the command to the wrong window.  For example, suppose a frame shows 2 different windows, each containing a different C buffer.  Suppose you want to comment out a region in the buffer in the lower window.  You select the region, move the mouse up to the menu bar, select C > Comment Out Region, and watch in frustration as the operation is performed on the buffer in the upper window.  The focus had changed as you moved to the menu bar.

WMs that support focus-follows-mouse together with raise-on-focus have a similar issue.  (Focus-follows-mouse is probably best with raise-on-focus.)  They typically deal with that issue by (a) having a delay, (b) requiring the mouse to be stationary, or (c) both, before transferring focus and raising.  That way, focus is less likely to be transferred when the user does not wish it.  My current WM implements (a) with something like a 0.5s delay.

So, I'm suggesting that (a) and/or (b) be implemented for mouse-autoselect-window.  Perhaps the variable could have a numeric value, meaning a delay.  A value of t might be equivalent to a value of 0.  A mouse-[123] in a window would still immediately change focus.

Comments?  Simon.

In GNU Emacs 22.0.50.1 (sparc-sun-solaris2.8, Motif Version 2.1.0)
 of 2006-06-15 on perth
X server distributor `Hummingbird Ltd.', version 11.0.100015
configured using `configure '--prefix=/rvcarma/marshals/software/slash/usr/local' '--with-x-toolkit=motif' 'CFLAGS=-g''

Important settings:
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