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.match_unreachable_pattern`

Match arm is unreachable after the wildcard.

Area 3, Logic; not declinable; the next step is usually the agent's.

example

function shout(label: Label) -> Label {    return match label {        "" -> "unnamed"        _ -> label        "quiet" -> "QUIET"    }}

jadpo checkcheck failed: 1 error, 2 files

error This arm never runs

--> main.jadpo:5:9

  |4 |         _ -> label  |         - matches everything left5 |         "quiet" -> "QUIET"  |         ^^^^^^^ after `_`

reason: _ matches every value the arms above it don't, so no arm after it runs.
next: Move this arm above _ (agent)
rule: type.match_unreachable_pattern
help: https://jadpo.dev/docs/errors/type.match_unreachable_pattern

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