proposal: a declared reopen returns the source when its target is retired - #48
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…ired A retired target stops blocking its source (proposal 0024), so the source's one slot is freed. Where the create-from also declares a completion hook, nothing can refill it: the hook exists to move the source OFF the status its own trigger qualifies on, and a lifecycle graph declares no edge back - so the source never re-qualifies and no event ever fires again. An event-only rule has no reissue path at all, and nothing says so. This proposes the hook's inverse on the same rule - where the source RETURNS when a target it produced is retired - so the reissue becomes the ordinary path: a real transition of the source, announced on the source's own channel, which the trigger already listens to. Nothing new declares what "retired" means: it is the same stage classification the guard reads, asked from the other end. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
A retirement is delivered at-least-once, so it can arrive again after the replacement already exists - and by then the source is standing at sourceStatus once more, because the reissue put it there. The standing-status test alone would re-open a source with a live target against it. The reopen now runs exactly when a creation would be allowed through. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
A create-from triggered only by a button carries no at-most-once guard, so nothing blocks a replacement - the button is itself the reissue, and there is no trigger for a reopen to re-fire. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
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proposals/0025-declared-reopen-on-retire.md.Follow-up to 0024 (a retired target stops blocking its source), which left one combination unreachable.
The gap. An event-driven create-from may declare a completion hook — the status the SOURCE moves to once the target exists. It exists precisely so the guard-claimed source stops matching its own trigger. 0024 then made a retired target stop blocking, which frees the source's slot. Put the two together and the door is unlocked with nobody able to knock: the source stands at the post-generation status, a lifecycle graph declares no edge back, so the source never transitions through the qualifying status again and no qualifying event is ever published. Where a button is also declared a person can click it; an event-only rule — the shape the event axis exists for — has no reissue path at all, and nothing says so.
What this proposes. The hook's inverse on the same rule: where the source returns when a target it produced is retired. Retiring the target returns the source, which is a real transition announced on the source's own channel, so the ordinary trigger re-fires, the guard steps over the retired target, and the replacement is minted. The reissue is the ordinary path — assembled from rules already in the language, not a second creation route with semantics of its own. Nothing new declares what "retired" means: it is the same
stage:classification the guard reads, asked from the other end.Idempotence is by state, not a marker: the reopen acts only while the source still stands at that rule's own completion status. And whether the replacement is immediate stays the trigger's decision — returning the source to an earlier status (a draft, for correction) makes the reissue reviewable rather than automatic.
The two alternatives are recorded in the proposal: having the target's retirement re-deliver the source's qualifying event (fabricates a transition nobody made, and re-fires every other consumer of that channel), and documenting-plus-warning (honest, but leaves the automation inexpressible).
Numbered 0025 — 0021–0024 are taken by open PRs; renumber as you see fit.
Reference implementation: eclipse-dirigible/dirigible#6868.