⎕STOP Stop List

Nomadic system function to stop functions or operators by setting 'break points'. Used with a numeric left argument, and the text name of a function, operator or method as the right argument, it will halt the function or operator before executing the line number(s) given in the list.

A left argument of 0, or an empty vector, removes stop control.

Used without a left argument, the current stop settings are returned.

To use ⎕STOP on a method of a class, the right argument should be the fully-qualified method name (i.e. the class name, a period, and the method name).

Note that, under desktop editions of APLX, the interpreter will bring up the Debugger window when a stop point is reached.