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E-TIMER-NAME-DUPLICATE

Two <onTimeout> elements in one state-child share a name=.

Error Compile-time SPEC §51.0.M (normative)

What it means

Timer names are scope-local to the state-child body and must be unique within it, because name= is what cancelTimer("…") targets. Two timers with one name make the cancel call ambiguous — it could plausibly cancel either or both — so the collision is rejected at the declaration.

Minimal reproducer

This is the exact source compiled against the linked compiler and verified to produce E-TIMER-NAME-DUPLICATE. 

<program title="p">
    type Phase:enum = { Idle, Busy }
    <engine for=Phase initial=.Idle>
        <Idle rule=(.Busy)>
            <onTimeout name="retry" after=1000ms to=.Busy/>
            <onTimeout name="retry" after=2000ms to=.Busy/>
            idle
        </>
        <Busy rule=(.Idle)>busy</>
    </>
</>

How to fix

  1. Rename one of the timers. Distinct names make every cancelTimer() call unambiguous.
  2. Drop name= from the one you never cancel. An unnamed timer is index-keyed and uncancellable, which is fine when nothing cancels it.

Related

Specification

Normative text: §51.0.M, §19.13, §34. Spec lives at compiler/SPEC.md .

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