Jadpo is experimental and not ready for production. These docs follow the compiler's main branch as of 30 Oct 2026. What's built · Install 0.1.0
jadpo
Reference: Policy

Policy · rule

policy.subject_duplicate

Grant names the same caller twice.

Area 9, Policy; not declinable; the next step is usually the agent's.

example
type Handle = Text {    max_length: 40}entity User {    id: Uuid    handle: Handle {        unique: true    }}principal {    user: {        subject: User.handle    }}entity Note {    id: Uuid    owner_id: User.id {        on_delete: OnDelete.cascade    }    policy: {        read: [owner_id, Access.authenticated, owner_id]    }}
text
error: `owner_id` is listed twice --> main.jadpo:25:48   |25 |         read: [owner_id, Access.authenticated, owner_id]   |                                                ^^^^^^^^ listed again  reason: A grant list means "any of these", so naming someone twice adds nothing and hides which line was meant.  next: Remove the second `owner_id` (agent)  rule: policy.subject_duplicate  help: https://jadpo.dev/docs/errors/policy.subject_duplicatecheck failed: 1 error, 1 file

Markdown for agents: /docs/errors/policy.subject_duplicate.md.Built from Jadpo main at a707efb.