calldebugger - enter Simula debugger from program
Enter the Simula debugger under program control.
external procedure Calldebugger;
if pointer == None then
Magnus Taube, Lund University.
Start the Simula debugger as if the program was interrupted
with a ctrl-\. The program may be continued after the
debugging session. Notice that this procedure acts as a
no-op if the program is not linked with the Simula debugger.