### SpanKind is the type of span. Can be used to specify additional relationships between spans
### in addition to a parent/child relationship.
###

## > Unspecified. Do NOT use as default.
## > Implementations MAY assume SpanKind to be `INTERNAL` when receiving `UNSPECIFIED`.
##
const UNSPECIFIED = 0;

## > Indicates that the span represents an internal operation within an application,
## > as opposed to an operation happening at the boundaries. Default value.
##
const INTERNAL = 1;

## > Indicates that the span covers server-side handling of an RPC or other
## > remote network request.
##
const SERVER = 2;

## > Indicates that the span describes a request to some remote service.
##
const CLIENT = 3;

## Indicates that the span describes a producer sending a message to a broker.
## > Unlike `CLIENT` and `SERVER`, there is often no direct critical path latency relationship
## > between producer and consumer spans. A `PRODUCER` span ends when the message was accepted
## > by the broker while the logical processing of the message might span a much longer time.
##
const PRODUCER = 4;

## > Indicates that the span describes consumer receiving a message from a broker.
## > Like the `PRODUCER` kind, there is often no direct critical path latency relationship
## > between producer and consumer spans.
const CONSUMER = 5;

## The `default` function returns the preferred default spankind if/when none is
## specified
##
fn make_default() with
  INTERNAL
end;