vendor/golang.org/x/net/trace/trace_go17.go

   1 // Copyright 2017 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 // +build go1.7
   6
   7 package trace
   8
   9 import "context"
  10
  11 // NewContext returns a copy of the parent context
  12 // and associates it with a Trace.
  13 func NewContext(ctx context.Context, tr Trace) context.Context {
  14         return context.WithValue(ctx, contextKey, tr)
  15 }
  16
  17 // FromContext returns the Trace bound to the context, if any.
  18 func FromContext(ctx context.Context) (tr Trace, ok bool) {
  19         tr, ok = ctx.Value(contextKey).(Trace)
  20         return
  21 }