feat: add get to iterator interface (#111)

Author: uncommon-nickname

include/rusty_iterators/interface.hpp

@@ -121,6 +121,12 @@ class IterInterface
         requires ForEachFunctor<T, Functor>
     auto forEach(Functor&& f) -> void;
 
+    template <size_t LB>
+    auto get() -> Skip<T, Derived>;
+
+    template <size_t LB, size_t UB>
+    auto get() -> Take<T, Skip<T, Derived>>;
+
     template <class Functor>
         requires InspectFunctor<T, Functor>
     [[nodiscard]] auto inspect(Functor&& f) -> Inspect<T, Functor, Derived>;
@@ -352,6 +358,20 @@ auto rusty_iterators::interface::IterInterface<T, Derived>::forEach(Functor&& f)
     }
 }
 
+template <class T, class Derived>
+template <size_t LB>
+auto rusty_iterators::interface::IterInterface<T, Derived>::get() -> Skip<T, Derived>
+{
+    return self().skip(LB);
+}
+
+template <class T, class Derived>
+template <size_t LB, size_t UB>
+auto rusty_iterators::interface::IterInterface<T, Derived>::get() -> Take<T, Skip<T, Derived>>
+{
+    return self().skip(LB).take(UB);
+}
+
 template <class T, class Derived>
 template <class Functor>
     requires rusty_iterators::concepts::InspectFunctor<T, Functor>

tests/iterator.test.cpp

@@ -395,3 +395,19 @@ TEST(TestIterator, TestProductOnMapIterator)
 
     ASSERT_EQ(it.product(), 2 * 4 * 6 * 8);
 }
+
+TEST(TestIterator, TestGetWithLowerBound)
+{
+    auto vec = std::vector{1, 2, 3, 4};
+    auto it  = LazyIterator{vec}.get<2>();
+
+    EXPECT_THAT(it.collect(), ElementsAreArray({3, 4}));
+}
+
+TEST(TestIterator, TestGetWithUbAndLb)
+{
+    auto vec = std::vector{1, 2, 3, 4};
+    auto it  = LazyIterator{vec}.get<1, 2>();
+
+    EXPECT_THAT(it.collect(), ElementsAreArray({2, 3}));
+}