solanaceae_util/solanaceae/util/span.hpp
2024-03-28 15:34:43 +01:00

40 lines
964 B
C++

#pragma once
#include <cstdint>
#include <stdexcept>
#include <vector>
// non owning view
template<typename T>
struct Span final {
const T* ptr {nullptr};
uint64_t size {0};
constexpr Span(void) {}
constexpr Span(const T* ptr_, uint64_t size_) : ptr(ptr_), size(size_) {}
constexpr explicit Span(const std::vector<T>& vec) : ptr(vec.data()), size(vec.size()) {}
explicit operator std::vector<T>() const {
return std::vector<T>{ptr, ptr+size};
}
constexpr const T& operator[](uint64_t i) const {
if (i > size) {
throw std::out_of_range("accessed span out of range");
}
return ptr[i];
}
constexpr const T* cbegin(void) const { return ptr; }
constexpr const T* cend(void) const { return ptr+size; }
constexpr const T* begin(void) const { return ptr; }
constexpr const T* end(void) const { return ptr+size; }
constexpr bool empty(void) const { return ptr == nullptr || size == 0; }
};
// useful alias
using ByteSpan = Span<uint8_t>;