Module Trace_core.Collector

A global collector.

The collector, if present, is responsible for collecting messages and spans, and storing them, recording them, forward them, or offering them to other services and processes.

type Trace_core__.Types.span +=
  1. | Span_dummy
val dummy_span : Trace_core__.Types.span

A fake span that never emits data. All collectors should handle this span by doing nothing.

module Callbacks : sig ... end
type t =
  1. | C_none
    (*

    No collector.

    *)
  2. | C_some : 'st * 'st Callbacks.t -> t
    (*

    Collector with a state and some callbacks.

    *)

Definition of a collector.

This is only relevant to implementors of tracing backends; to instrument your code you only need to look at the Trace module.

The definition changed since 0.11 to a record of callbacks + a state

val is_some : t -> bool