diff options
Diffstat (limited to 'to_string.hpp')
| -rw-r--r-- | to_string.hpp | 47 |
1 files changed, 29 insertions, 18 deletions
diff --git a/to_string.hpp b/to_string.hpp index 2d18589..63b52ab 100644 --- a/to_string.hpp +++ b/to_string.hpp @@ -18,27 +18,28 @@ constexpr auto digit_count = sizeof(digits) / sizeof(digits[0]); * @tparam N Number to convert * @tparam base Desired base, can be from 2 to 36 */ -template<auto N, unsigned int base, typename char_type, +template<auto N, int base, typename char_type, std::enable_if_t<std::is_integral_v<decltype(N)>, int> = 0, std::enable_if_t<(base > 1 && base < digit_count), 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); + for (auto n = N; n; len++, n /= base); return len; }())] = {}; + public: /** * Constructs the object, filling `buf` with the string representation of N. */ constexpr to_string_t() noexcept { + auto ptr = end(); + *--ptr = '\0'; if (N != 0) { - auto ptr = buf + sizeof(buf) / sizeof(buf[0]); - *--ptr = '\0'; - for (auto n = N < 0 ? -N : N; n; n /= base) - *--ptr = digits[n % base]; + for (auto n = N; n; n /= base) + *--ptr = digits[(N < 0 ? -1 : 1) * (n % base)]; if (N < 0) *--ptr = '-'; } else { @@ -47,20 +48,30 @@ 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 const auto data() const noexcept { return buf; } + constexpr auto& operator[](unsigned int i) noexcept { return buf[i]; } + constexpr const auto& operator[](unsigned int i) const noexcept { return buf[i]; } + constexpr auto& front() noexcept { return buf[0]; } + constexpr const auto& front() const noexcept { return buf[0]; } + constexpr auto& back() noexcept { return buf[size() - 1]; } + constexpr const auto& back() const noexcept { return buf[size() - 1]; } + // Iterators + constexpr auto begin() noexcept { return buf; } + constexpr const auto begin() const noexcept { return buf; } + constexpr auto end() noexcept { return buf + size(); } + constexpr const auto end() const noexcept { return buf + size(); } }; /** * Simplifies use of `to_string_t` from `to_string_t<N>()` to `to_string<N>`. */ -template<auto N, unsigned int base = 10, typename char_type = char> +template<auto N, int base = 10, typename char_type = char> constexpr to_string_t<N, base, char_type> to_string; - + #endif // TCSULLIVAN_TO_STRING_HPP_ |