How to bind a command to mouse-1 properly?

[Dmitry Gutov]

Hi all,

If I bind a command other than `mouse-set-point' to [mouse-1], the mark
is active after the mouse click. Example:

1. (global-set-key [mouse-1] (lambda (e) (interactive "e")
(mouse-set-point e)))

2. Click somewhere in a buffer.

3. Press `C-s', then search for some existing word.

=> the region will be active and span from the position of the click to
the new point.

If, on the other hand,

1. (global-set-key [mouse-1] 'mouse-set-point)

2, 3: same as before.

=> the region is not active.

Should I (setq deactivate-mark t) inside the command body?

--Dmitry