Files
mysysy/src/include/range.h

63 lines
1.5 KiB
C++

#pragma once
#include <iterator>
namespace sysy {
/*!
* \defgroup utility Utilities
* @{
*/
/*!
* \brief `range` is an simple wrapper of an iterator pair [begin, end)
*
* Example usage
*
* ```cpp
* vector<int> v = {1,2,3};
* auto rg = make_range(v);
* for (auto v : rg)
* cout << v << '\n';
* ```
*/
template <typename IterT> struct range {
using iterator = IterT;
using value_type = typename std::iterator_traits<iterator>::value_type;
using reference = typename std::iterator_traits<iterator>::reference;
private:
iterator b;
iterator e;
public:
explicit range(iterator b, iterator e) : b(b), e(e) {}
iterator begin() { return b; }
iterator end() { return e; }
iterator begin() const { return b; }
iterator end() const { return e; }
auto size() const { return std::distance(b, e); }
auto empty() const { return b == e; }
};
//! create `range` object from iterator pair [begin, end)
template <typename IterT> range<IterT> make_range(IterT b, IterT e) {
return range(b, e);
}
//! create `range` object from a container who has `begin()` and `end()` methods
template <typename ContainerT>
range<typename ContainerT::iterator> make_range(ContainerT &c) {
return make_range(c.begin(), c.end());
}
//! create `range` object from a container who has `begin()` and `end()` methods
template <typename ContainerT>
range<typename ContainerT::const_iterator> make_range(const ContainerT &c) {
return make_range(c.begin(), c.end());
}
/*!
* @}
*/
} // namespace sysy