diff options
Diffstat (limited to 'asl/option.hpp')
| -rw-r--r-- | asl/option.hpp | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/asl/option.hpp b/asl/option.hpp index ebb9eef..0c816f4 100644 --- a/asl/option.hpp +++ b/asl/option.hpp @@ -429,6 +429,53 @@ public: }
return un_cvref_t<result_of_t<F(T)>>{};
}
+
+ template<typename F>
+ constexpr auto transform(F&& f) &
+ {
+ using U = un_cvref_t<result_of_t<F(T&)>>;
+ if (has_value())
+ {
+ return option<U>{ invoke(ASL_FWD(f), value()) };
+ }
+ return option<U>{};
+ }
+
+ template<typename F>
+ constexpr auto transform(F&& f) const&
+ {
+ using U = un_cvref_t<result_of_t<F(const T&)>>;
+ if (has_value())
+ {
+ return option<U>{ invoke(ASL_FWD(f), value()) };
+ }
+ return option<U>{};
+ }
+
+ template<typename F>
+ constexpr auto transform(F&& f) &&
+ {
+ using U = un_cvref_t<result_of_t<F(T)>>;
+ if (has_value())
+ {
+ return option<U>{ invoke(ASL_FWD(f), ASL_MOVE(value())) };
+ }
+ return option<U>{};
+ }
+
+ template<typename F>
+ constexpr option or_else(F&& f) const&
+ requires is_same<un_cvref_t<result_of_t<F()>>, option>
+ {
+ return has_value() ? *this : invoke(ASL_FWD(f));
+ }
+
+ template<typename F>
+ constexpr option or_else(F&& f) &&
+ requires is_same<un_cvref_t<result_of_t<F()>>, option>
+ {
+ return has_value() ? ASL_MOVE(*this) : invoke(ASL_FWD(f));
+ }
};
template<typename T>
|