Ruled 2026-10-04: guard all errors. The errors that set NODE-ERROR and
let the line run on now stop it at once, with a message.
- A store of a non-zero code to NODE-ERROR is a trap, a sixth kind of
fault: nothing after it executes, the return stack is emptied, and the
data stack is left as the word left it. Not attached, NODE-ERROR is
plain memory, as the tests below the prompt use it.
- The capsule's words store a code where they stored -1, and the prompt's
(RAISED) prints its message: Negative count, Not a number, Number too
long, Not a character, Dictionary full, Name missing, Control structure
mismatch, Control structures too deep.
- ' and COMPILE and [COMPILE] of a word that is not there say
UNKNOWN WORD: 'xxx', as the interpreter does.
- tests: the trap in test_exec.c; every message from the prompt, with the
rest of the line not run and the stack kept, in test_host_quit.c.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>