8 #ifndef TREELITE_OPTIONAL_H_ 9 #define TREELITE_OPTIONAL_H_ 16 optional() : empty_{}, has_value_{
false} {}
18 explicit optional(
const T& input_value) : value_{input_value}, has_value_{
true} {}
33 explicit operator bool()
const {
39 const T& operator*()
const {
45 optional& operator=(
const T& new_value) {
62 #endif // TREELITE_OPTIONAL_H_