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

ReferenceErrors

`type.rule_not_condition`

Rule's condition isn't a Bool.

Area 2, Values and types; not declinable; the next step is usually the agent's.

A rule holds or it doesn't, so its condition is a Bool:

example

type Stock = Int {    min: 0}type PriceBand = Object {    low: Stock    high: Stock    rule spread: high - low}

jadpo checkcheck failed: 1 error, 1 file

error The rule spread isn't a condition

--> main.jadpo:8:18

  |8 |     rule spread: high - low  |                  ^^^^^^^^^^ this is `Int`

reason: A rule holds for a value or it doesn't, so its condition is a Bool: a comparison such as high > low, or several joined with and, or and not.
next: Write spread as a comparison of PriceBand's fields (agent)
rule: type.rule_not_condition
help: https://jadpo.dev/docs/errors/type.rule_not_condition

Markdown for agents: /docs/errors/type.rule_not_condition.md.Built from Jadpo main at aee2e8f.