Jadpo is experimental and not ready for production. These docs follow the compiler's main branch as of 5 Nov 2026. What's built · Install 0.3.0
jadpo
ReferenceErrors

ErrorsFailures · rule

failure.duplicate_declaration

Failure is listed twice after fails.

Area 4, Failures; not declinable; the next step is usually the agent's.

example
type Note = Text {}type Refused = Failure {    kind: FailureKind.rejected}action execute(note: Note) fails Refused, Refused -> Note {    reject Refused}
jadpo checkcheck failed: 1 error, 1 file

error Refused is listed twice after fails

--> main.jadpo:7:43

  |7 | action execute(note: Note) fails Refused, Refused -> Note {  |                                           ^^^^^^^ listed again  |                                  ------- first listed here
reason
fails lists each failure that can leave once.
next
Remove the second Refused (agent)
rule
failure.duplicate_declaration
help
https://jadpo.dev/docs/errors/failure.duplicate_declaration

Markdown for agents: /docs/errors/failure.duplicate_declaration.md.Built from Jadpo main at aee2e8f.