LDC-E1313 — Transition out of a terminal state

What it means

A terminal state ends the run: marking a state terminal promises that nothing leaves it. A transition that starts from such a state breaks that promise — kept silent, the terminality would be a mere comment — so the compiler stops at the transition.

The repair is to honor the ending: point the transition at a non-terminal state, or drop the terminal mark if the state genuinely has somewhere to go. Ends stay ends.

Example

Arxo Law

language "law.core" version "0.2";
package demo.diagnostics version "0.1.0";
namespace "urn:law:demo:diagnostics";

entity Tenant;
procedure Review(t: Tenant) {
    state Open initial;
    state Mid terminal;
    state Closed terminal;
    transition Back {
        from Mid;
        to Closed;
    }
}

Fix

Arxo Law

language "law.core" version "0.2";
package demo.diagnostics version "0.1.0";
namespace "urn:law:demo:diagnostics";

entity Tenant;
procedure Review(t: Tenant) {
    state Open initial;
    state Closed terminal;
    transition Decide {
        from Open;
        to Closed;
    }
}

Engine message

The engine reports this in its own wording:

Output

example.law:10:16: error LDC-E1313: transition "Back" exits terminal state "Mid" — terminality would otherwise be a comment (§160)

Related

• Procedures — states, transitions, and how a procedure runs.
• LDC-E1312 — transitions must name declared states.