The current DSL Showcase contains an overlays source example with open/close behavior and state. It is useful for explaining an interaction flow as a sequence of semantic intent:
- A visible control emits an explicit event.
- The event targets a named node/state change.
- The next tree/presentation is produced by the runtime and target renderer.
- A later control reverses or changes that state.
This is different from treating an overlay as a browser-only DOM trick. The source can establish that the current compiler understands the declarations; a target acceptance test must establish focus behavior, device presentation, dismissal behavior, and any caller/permission boundary.
Test a flow as observations
For an actual product flow, record each step as an observable fact:
| Step | Record |
|---|---|
| Entry | target, runtime version, starting page/session state |
| Trigger | exact node/event the reviewer invoked |
| Intermediate result | visible tree/presentation and expected state change |
| Exit | close/back/dismiss behavior and final state |
| Boundary | any required caller identity, data scope, or target limitation |
Do not say that a Showcase source file “has passed a flow test” unless that exact registered target, version, and sequence were run. For event authoring, see Events, navigation, and visibility; for session updates, see Sessions, patches, and scenes.