Purpose With Leave you can stop the flow of an InputScript. The current screen is the one displayed. In contrast to Return, there is no return to the initial (start) transaction.
Example Leave
Format Leave
& Tricks
In general it only makes sense to use Leave if you have used Enter. If you use Leave to stop an InputScript, following a  Screen-command without Enter, the current screen will be displayed without GuiXT Script execution, and this is not usually what you want.
Components GuiXT