trace_go16.go 602 B

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  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. // +build !go1.7
  5. package trace
  6. import "golang.org/x/net/context"
  7. // NewContext returns a copy of the parent context
  8. // and associates it with a Trace.
  9. func NewContext(ctx context.Context, tr Trace) context.Context {
  10. return context.WithValue(ctx, contextKey, tr)
  11. }
  12. // FromContext returns the Trace bound to the context, if any.
  13. func FromContext(ctx context.Context) (tr Trace, ok bool) {
  14. tr, ok = ctx.Value(contextKey).(Trace)
  15. return
  16. }