Constant

1 Version

Pure source with no input port: emits a fixed deploy-time literal forever, re-sending the same value on every downstream demand. The configured value carries its own type tag, so it pins the output stream type t to a concrete type rather than leaving it free.

How it fits

Typical backends

Tunable threshold compared against an upstream numeric stream.

Static label packed alongside dynamic fields into a record.

Default operand merged alongside a real signal stream.

Caveats

Hard constraintThe output type t is fixed by the configured value's type tag, not inferred from the consumer; wiring it into a port that expects a different type is a mismatch, not a coercion.
Parameter interactionThe value is captured at deploy time and carries both payload and type tag together, so the same configuration simultaneously fixes the emitted literal and the output stream type; changing it requires redeploying the backend.
I/O contractThere is no input port, yet it still occupies a stream slot and emits one repeated value per downstream demand, an unbounded constant stream.

Versions

61244b84defaultlatestTransformation
10/12/2023