pub fn parse_traceparent(value: &[u8]) -> Option<(TraceId, SpanId, u8)>Expand description
Parse a traceparent value: version-traceid-parentid-flags, as
lowercase hex.
Refused, as the specification says it must be: version ff; a trace id or
parent id of all zeroes; uppercase hex; a version-00 value with anything
after the flags. A version this side does not know is read as 00 would
be, provided what follows the flags starts a new field – the
specification’s provision for versions not yet written.