func NewTracer(root opentracing.Span) *Tracer {
	return &Tracer{
		root:  root,
		spans: make([]opentracing.Span, 0, 32),
	}
}
func NewTracer(root opentracing.Span) *Tracer {
	return &Tracer{
		root:  root,
		spans: make([]opentracing.Span, 0, 32),
	}
}
func NewTracer ( root opentracing . Span ) * Tracer { return & Tracer { root : root , spans : make ( [ ] opentracing . Span , 0 , 32 ) , } }
// NewTracer returns a new tracer with the specified root span.
NewTracer returns a new tracer with the specified root span .