The trap mechanism in Mumps has similarities to the exception mechanism in many other language.
Most examples I have seen of trap usage is for catching unintentional errors.
Is there also a way intentionally trigger an error, which can be caught by a trap, in a way that is similar to throwing an exception?
I am working with GT.M V7.0. I’m learning about traps from here:
http://tinco.pair.com/bhaskar/gtm/doc/books/pg/UNIX_manual/ch13s06.html
You can do this by setting the $ECODE variable.
See also https://docs.yottadb.com/ProgrammersGuide/errproc.html#ecode.
This is YottaDB but I think it will work for GT.M too.
SET $ECODE=",U13-User defined error trap,"
A simple thing that should work too: S X=1/0