add Chapter18

Chapter18/cib/libs/sc/fwd.hpp

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+#pragma once
+
+#include <stdx/compiler.hpp>
+#include <stdx/ct_string.hpp>
+
+#include <concepts>
+#include <type_traits>
+
+namespace sc {
+template <std::signed_integral auto value>
+constexpr static std::integral_constant<decltype(value), value> int_{};
+
+template <std::unsigned_integral auto value>
+constexpr static std::integral_constant<decltype(value), value> uint_{};
+
+template <bool value>
+constexpr static std::integral_constant<bool, value> bool_{};
+
+template <char value>
+constexpr static std::integral_constant<char, value> char_{};
+
+template <auto enumValue>
+    requires std::is_enum_v<decltype(enumValue)>
+constexpr static std::integral_constant<decltype(enumValue), enumValue> enum_{};
+
+template <typename T> struct type_name {
+    constexpr explicit type_name(T) {}
+    constexpr type_name() = default;
+};
+
+template <typename T> constexpr static type_name<T> type_{};
+
+template <typename CharT, CharT... chars> struct string_constant;
+
+inline namespace literals {
+template <stdx::ct_string S> CONSTEVAL auto operator""_sc() {
+    return stdx::ct_string_to_type<S, string_constant>();
+}
+} // namespace literals
+
+template <typename T>
+concept sc_like = requires(T const &t) {
+    t.apply([]<typename StringType>(StringType, auto const &...) {});
+};
+} // namespace sc
+using sc::literals::operator""_sc;