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

ErrorsValues and types · rule

type.primitive_signature

Signature uses a built-in type directly.

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

example
type Title = Text {    max_length: 200}function normalise(value: Text) -> Title {    return Title(value)}
jadpo checkcheck failed: 1 error, 1 file

error This parameter uses Text directly

--> main.jadpo:5:27

  |5 | function normalise(value: Text) -> Title {  |                           ^^^^ a built-in type
reason
Functions, actions and queries take and return named types, so each value says what it means and carries its rules; Text says neither.
next
Declare a named type built on Text and use it here (agent)
rule
type.primitive_signature
help
https://jadpo.dev/docs/errors/type.primitive_signature

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