Basic Characteristics RAPID

Error Recovery Basic Characteristics RAPID
occurs in a routine that does not contain an error handler (or if the error is explicitly
propagated using the raise instruction) the same error is raised again at the point where
the routine was called – the error is propagated. If the top of the call chain is reached
without any error handler being found, the system error handler is called. The system
error handler just reports the error and stops the execution. If an error is propagated
from a trap routine this will result in immediate termination of the execution by the system
error handler.
Error recovery is not available for instructions in the backward handler. Such errors are
always propagated to the system error handler.
In addition to errors detected and raised by the robot, a program can explicitly raise
errors using the RAISE instruction. This facility can be used to recover from complex
situations. It can, for example, be used to escape from deeply-nested code positions.
Error numbers 1-90 may be used in the raise instruction. Explicitly-raised errors are
treated exactly like errors raised by the system.
Note that it is not possible to recover from or respond to errors that occur within an error
clause. Such errors are always propagated to the system error handler.
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