package testdata import ( "context" "fmt" ) // This returns the head state. // It does a full copy on head state for immutability. func headState(ctx context.Context) { ctx, span := StartSpan(ctx, "blockChain.headState") fmt.Print(span) return } // StartSpan -- func StartSpan(ctx context.Context, name string) (context.Context, int) { return ctx, 42 }