ir_sink design

Design goal

Give applications one short import for the sinks that feed the report pipeline, without a second implementation of them.

Mathematical background

Each function of ir_sink equals an event function: in_memory = InMemorySink::new, jsonl = JsonlSink::new, jsonl_stream = streaming_jsonl, tee = tee. The package is the identity on behaviour; it only renames.

Design decisions

A facade, not a second sink layer

Problem. Examples and applications that only want “events into JSONL for the report” should not need to learn the full event surface. Choice. Four delegating functions. Why. Every behaviour is defined once, in event, so the facade cannot drift; the types it returns are the event types, so values from both packages mix freely.

Correctness and invariants

• Every function returns exactly what the corresponding event function returns.
• ir_sink depends only on event.

Alternatives rejected

• Re-exporting with pub using. Would also work; named functions keep the short names (jsonl_stream) independent of event’s names.

Boundaries

• No sink types of its own, no file IO, no parsing.