POP KEY Command
Restores ON KEY LABEL assignments that were placed on the stack with PUSH KEY.
Clears all current key assignments defined with ON KEY LABEL and clears all key assignments defined with ON KEY LABEL from the stack.
POP KEY, when used with PUSH KEY, lets you save a set of key assignments created with ON KEY LABEL commands, make changes to the key assignments with more ON KEY LABEL commands, and then restore the original key assignments.
Key assignments take up memory, so every POP KEY should have a corresponding PUSH KEY to make sure your application's memory usage does not grow unnecessarily.
For more information on placing ON KEY LABEL commands on the stack, see.