|
|
|
@ -18,15 +18,16 @@
|
|
|
|
|
template<auto N, unsigned int base, typename char_type,
|
|
|
|
|
std::enable_if_t<std::is_integral_v<decltype(N)>, int> = 0,
|
|
|
|
|
std::enable_if_t<(base > 1 && base < 37), int> = 0>
|
|
|
|
|
struct to_string_t {
|
|
|
|
|
class to_string_t {
|
|
|
|
|
// The lambda calculates what the string length of N will be, so that `buf`
|
|
|
|
|
// fits to the number perfectly.
|
|
|
|
|
char_type buf[([] {
|
|
|
|
|
char_type buf[([]() constexpr noexcept {
|
|
|
|
|
unsigned int len = N > 0 ? 1 : 2;
|
|
|
|
|
for (auto n = N < 0 ? -N : N; n; len++, n /= base);
|
|
|
|
|
return len;
|
|
|
|
|
}())] = {};
|
|
|
|
|
|
|
|
|
|
public:
|
|
|
|
|
/**
|
|
|
|
|
* Constructs the object, filling `buf` with the string representation of N.
|
|
|
|
|
*/
|
|
|
|
@ -44,14 +45,24 @@ struct to_string_t {
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// Support implicit casting to `char *` or `const char *`.
|
|
|
|
|
constexpr operator char_type *() { return buf; }
|
|
|
|
|
constexpr operator const char_type *() const { return buf; }
|
|
|
|
|
|
|
|
|
|
// Support range-based for loops
|
|
|
|
|
constexpr auto begin() { return buf; }
|
|
|
|
|
constexpr auto begin() const { return buf; }
|
|
|
|
|
constexpr auto end() { return buf + sizeof(buf) / sizeof(buf[0]); }
|
|
|
|
|
constexpr auto end() const { return buf + sizeof(buf) / sizeof(buf[0]); }
|
|
|
|
|
constexpr operator char_type *() noexcept { return buf; }
|
|
|
|
|
constexpr operator const char_type *() const noexcept { return buf; }
|
|
|
|
|
|
|
|
|
|
constexpr auto size() const noexcept { return sizeof(buf) / sizeof(buf[0]); }
|
|
|
|
|
// Element access
|
|
|
|
|
constexpr auto data() noexcept { return buf; }
|
|
|
|
|
constexpr auto data() const noexcept { return buf; }
|
|
|
|
|
constexpr auto operator[](unsigned int i) noexcept { return buf[i]; }
|
|
|
|
|
constexpr auto operator[](unsigned int i) const noexcept { return buf[i]; }
|
|
|
|
|
constexpr auto front() noexcept { return buf[0]; }
|
|
|
|
|
constexpr auto front() const noexcept { return buf[0]; }
|
|
|
|
|
constexpr auto back() noexcept { return buf[size() - 1]; }
|
|
|
|
|
constexpr auto back() const noexcept { return buf[size() - 1]; }
|
|
|
|
|
// Iterators
|
|
|
|
|
constexpr auto begin() noexcept { return buf; }
|
|
|
|
|
constexpr auto begin() const noexcept { return buf; }
|
|
|
|
|
constexpr auto end() noexcept { return buf + size(); }
|
|
|
|
|
constexpr auto end() const noexcept { return buf + size(); }
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
/**
|
|
|
|
@ -59,5 +70,5 @@ struct to_string_t {
|
|
|
|
|
*/
|
|
|
|
|
template<auto N, unsigned int base = 10, typename char_type = char>
|
|
|
|
|
constexpr to_string_t<N, base, char_type> to_string;
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
#endif // TCSULLIVAN_TO_STRING_HPP_
|
|
|
|
|