Valuesend

Valuesend is a term used in some streaming interfaces and data-processing protocols to mark the end of a sequence of values transmitted in a single stream or message. It is not a universal language feature but a protocol-level marker that can appear as a dedicated frame, token, or packet in various implementations.

Definition and purpose: The valuesend marker indicates that the producer has finished sending values for the current sequence, allowing the consumer to finalize the batch, flush buffers, and proceed to the next stage of processing. It is often paired with a value-containing frame or message that carries the actual data values.

Usage patterns: In data pipelines or remote procedure call streams, values are sent as a series of value frames or messages. When the producer is done, it transmits a valuesend frame. The consumer collects values until valuesend is observed, then processes the gathered data and moves on.

Implementation considerations: Ensure clear framing to distinguish values from markers, and handle partial transmissions or reconnection scenarios. Provide explicit errors if valuesend is received in an invalid state. Consider support for multiple concurrent value streams on a single connection, and implement timeouts or backpressure logic to avoid deadlocks.

Example: The sender emits a sequence of values, then signals completion:

emitValue(v1)

emitValue(v2)

emitValue(v3)

emitValuesend()

The receiver collects until valuesend is seen:

values = []

while true:

frame = readNext()

if frame.type == "value":

values.append(frame.data)

elif frame.type == "valuesend":

break

Process(values)

See also: end-of-stream, delimiters in streaming protocols, and related framing markers.