TraceContext.Context.extract: def of bend-trace-context@0.2.0.0
Import: import bend-trace-context@0.2.0.0/trace_context.bend as TraceContext
Lines 3027-3044 of bend-trace-context@0.2.0.0/trace_context.bend: https://jend.leeeet.dev/read.txt?path=bend-trace-context@0.2.0.0/trace_context.bend&start_line=3027&end_line=3044

import Base

# Extract the trace context of a received message from its carrier, with
# `base` as the context to keep when the message has no usable traceparent
# (spec #1, user stories 14, 15, 16, 24 and 25):
#   - no traceparent field keeps the base, TraceParentAbsent{};
#   - more than one traceparent field, whatever the case of their names, is
#     refused, and so is a single value that TraceParent.read refuses; the
#     base is kept, TraceParentRejected{error};
#   - an accepted value gives the incoming context and replaces the base: its
#     tracestate fields, whatever the case of their names, are read in
#     arrival order as their comma-joined combination, within the tracestate
#     input budget; refused fields are discarded whole, keeping the
#     traceparent;
#   - without an accepted traceparent, tracestate fields are not read.
# Laws: extract_absent, extract_repeated, extract_refused, extract_read,
# state_independent and received_bounds.
def Context.extract(+limits: Limits, +carrier: List<&2, Header>, base: Maybe<&2, BaseContext>) -> Extraction:
  Extract.parents(limits, Carrier.values(carrier, Carrier.traceparent_name()),
    Carrier.values(carrier, Carrier.tracestate_name()), base)

Uses (10):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Maybe
  https://jend.leeeet.dev/definition.txt?path=bend-trace-context@0.2.0.0/trace_context.bend&name=BaseContext
  https://jend.leeeet.dev/definition.txt?path=bend-trace-context@0.2.0.0/trace_context.bend&name=Carrier.traceparent_name
  https://jend.leeeet.dev/definition.txt?path=bend-trace-context@0.2.0.0/trace_context.bend&name=Carrier.tracestate_name
  https://jend.leeeet.dev/definition.txt?path=bend-trace-context@0.2.0.0/trace_context.bend&name=Carrier.values
  https://jend.leeeet.dev/definition.txt?path=bend-trace-context@0.2.0.0/trace_context.bend&name=Extract.parents
  https://jend.leeeet.dev/definition.txt?path=bend-trace-context@0.2.0.0/trace_context.bend&name=Extraction
  https://jend.leeeet.dev/definition.txt?path=bend-trace-context@0.2.0.0/trace_context.bend&name=Header
  https://jend.leeeet.dev/definition.txt?path=bend-trace-context@0.2.0.0/trace_context.bend&name=Limits