Lexikos/AutoHotkey_L — pull request #6 by russelldavis (2011-11-24 08:08:04+00:00)
Title: Add a new #InputGroup directive for controlling which generated inputs get ignored

To avoid infinite loops and other side effects, AHK ignores self-generated input events.
It does this by setting a sentinel value in the ExtraInfo field when sending input. In
previous versions, a single sentinel value was used for all scripts, making it impossible
for a script to send input that triggers a hotkey in another script.

The #InputGroup directive provides a way to change the sentinel, so that each script only
ignores input from the other scripts in the same input group.

A common use case for this is global key remapping. If script A remaps keys 1, 2, and 3
to X, script B can specify a different #InputGroup and set a hotkey for X that is
triggered by any of the keys remapped by script A.