Method IsPersistent

source/script.cpp:1257–1298

bool Script::IsPersistent()
{
	// Consider the script "persistent" if any of the following conditions are true:
	if (Hotkey::sHotkeyCount || Hotstring::sHotstringCount // At least one hotkey or hotstring exists.
		// No attempt is made to determine if the hotkeys/hotstrings are enabled, since even if they
		// are, it's impossible to detect whether #HotIf will allow them to ever execute.
		|| g_persistent // Persistent() has been used somewhere in the script.
		|| g_script.mTimerEnabledCount // At least one script timer is currently enabled.
		|| mOnClipboardChange.Count() // The script is monitoring clipboard changes.
		|| g_input // At least one active InputHook.
		|| IsWindowVisible(g_hWnd))
		return true;
	// OnMessage does not make the script persistent because:
	//  1) It has too many uses to assume that the author would want the script to be persistent
	//     (which would probably only be in cases where OnMessage is the main purpose of the script,
	//     such as if it just idles until a command is received via WM_COPYDATA or other message).
	//  2) It's often used in conjunction with a GUI, and in such cases it's probably more convenient
	//     to rely on other logic to keep the script running while the GUI is visible, and allow it to
	//     exit when the GUI is closed.
	//  3) Message monitors that are intended to keep the script running probably won't be removed,
	//     so checking the number of active monitors here at runtime doesn't offer much benefit vs.
	//     requiring the script to call Persistent() if needed.
	//  4) The only alternatives to OnMessage are generally window subclassing and hooks, which come
	//     with various problems, such as spamming ListLines, interacting badly with Pause/A_IsPaused
	//     (due to thread-starting messages passing through the window proc), and others.
	// Adding custom items to A_TrayMenu does not make the script persistent because:
	//  1) It could be something like a slight modification to a standard item's behaviour,
	//     or something else that isn't intended to keep the script running.
	//  2) Custom items usually aren't removed, so having checks for them at runtime is not as helpful
	//     as some of the conditions above, like timers and visible windows.  When they are removed, it
	//     is always a direct action of the code, not some external event.
	//  3) If adding custom items made the script persistent, it can be worked around by intercepting
	//     right-clicks on the tray icon and showing some other menu, but replicating the Pause/Suspend
	//     checkmarks and AddStandard() behaviour is surprisingly complicated.  By contrast, calling
	//     Persistent() before/after adding the custom items is trivial.
	for (GuiType* gui = g_firstGui; gui; gui = gui->mNextGui)
		if (IsWindowVisible(gui->mHwnd)) // A GUI is visible.
			return true;
	// Otherwise, none of the above conditions are true; but there might still be
	// one or more script threads running.  Caller is responsible for checking that.
	return false;
}