Make allocator and string_base compat easier to read and remove unneccessary concepts subdirectory

include/rexy/allocator.hpp

@@ -19,143 +19,12 @@
 #ifndef REXY_DEFAULT_ALLOCATOR_HPP
 #define REXY_DEFAULT_ALLOCATOR_HPP
 
-#include <cstddef> //ptrdiff_t, size_t
+#include "compat/allocator.hpp"
-#include <type_traits> //true_type, false_type
-#include <new>
-#include <limits> //numeric_limits
-
-#if __cplusplus >= 202002L
-	#include <memory> //allocator
-#endif
-
-#ifdef __cpp_concepts
-	#include "concepts/allocator.hpp"
-	#define REXY_ALLOCATOR_CONCEPT Allocator
-#else
-	#define REXY_ALLOCATOR_CONCEPT class
-#endif
-
-#include "rexy.hpp"
-#include "compat/standard.hpp"
-#include "compat/if_consteval.hpp"
 
 #include <type_traits> //declval
 
 namespace rexy{
 
-	template<class T>
-	struct allocator
-	{
-		using pointer = T*;
-		using const_pointer = const T*;
-		using void_pointer = void*;
-		using const_void_pointer = const void*;
-		using value_type = T;
-		using size_type = std::size_t;
-		using difference_type = ptrdiff_t;
-		using is_always_equal = std::true_type;
-		using propagate_on_container_copy_assignment = std::false_type;
-		using propagate_on_container_move_assignment = std::false_type;
-		using propagate_on_container_swap = std::false_type;
-
-		template<class U>
-		struct rebind{
-			using other = allocator<U>;
-		};
-
-	private:
-		constexpr bool has_overflow(size_type n)const{
-			return n > max_size();
-		}
-
-	public:
-		REXY_CPP20_CONSTEXPR allocator(void) = default;
-		REXY_CPP20_CONSTEXPR allocator(const allocator&) = default;
-		REXY_CPP20_CONSTEXPR allocator(allocator&&) = default;
-		template<class U>
-		constexpr allocator(const allocator<U>&)noexcept{}
-		REXY_CPP20_CONSTEXPR ~allocator(void) = default;
-
-		//'::operator new' is never a constexpr call as of C++23. However, 'std::allocator::allocate' *is* transiently constexpr as of C++20,
-		//even though it directly calls '::operator new' as is stated in the standard. Therefore, when evaluating this call with support for
-		//'if consteval', we can use the 'std::allocator::allocate' constexpr-ness when this is in a constant evaluation context.
-#if __cplusplus >= 202002L
-		REXY_CPP20_CONSTEXPR pointer allocate(size_type n){
-			size_type bytes = has_overflow(n) ? std::numeric_limits<size_type>::max() : n*sizeof(T);
-
-			REXY_if_consteval{
-					std::allocator<value_type> a;
-					const size_type num_items = n / sizeof(value_type);
-					return a.allocate(num_items);
-				}else{
-					if constexpr(alignof(T) <= __STDCPP_DEFAULT_NEW_ALIGNMENT__){
-						return reinterpret_cast<pointer>(::operator new(bytes));
-					}else{
-						return reinterpret_cast<pointer>(::operator new(bytes, static_cast<std::align_val_t>(alignof(T))));
-					}
-				} //if consteval
-		}
-
-
-		REXY_CPP20_CONSTEXPR void deallocate(pointer p, size_type n){
-			REXY_if_consteval{
-					std::allocator<value_type> a;
-					const size_type num_items = n / sizeof(value_type);
-					return a.deallocate(p, num_items);
-				}else{
-
-				#if !defined(__cpp_sized_deallocation)
-					//clang does not enable ::operator delete(void* ptr, std::size_t sz) by default for some reason
-					if constexpr(alignof(T) <= __STDCPP_DEFAULT_NEW_ALIGNMENT__){
-						::operator delete(p);
-					}else{
-						::operator delete(p, static_cast<std::align_val_t>(alignof(T)));
-					}
-				#else //__cpp_sized_deallocation
-					size_type bytes = has_overflow(n) ? std::numeric_limits<size_type>::max() : n*sizeof(T);
-					if constexpr(alignof(T) <= __STDCPP_DEFAULT_NEW_ALIGNMENT__){
-						::operator delete(p, bytes);
-					}else{
-						::operator delete(p, bytes, static_cast<std::align_val_t>(alignof(T)));
-					}
-				#endif //__cpp_sized_deallocation
-
-			} //if consteval
-
-		}
-#else //__cplusplus
-		REXY_CPP20_CONSTEXPR pointer allocate(size_type n){
-			size_type bytes = has_overflow(n) ? std::numeric_limits<size_type>::max() : n*sizeof(T);
-
-			if constexpr(alignof(T) <= __STDCPP_DEFAULT_NEW_ALIGNMENT__){
-				return reinterpret_cast<pointer>(::operator new(bytes));
-			}else{
-				return reinterpret_cast<pointer>(::operator new(bytes, static_cast<std::align_val_t>(alignof(T))));
-			}
-		}
-		REXY_CPP20_CONSTEXPR void deallocate(pointer p, size_type n){
-			#if !defined(__cpp_sized_deallocation)
-				//clang does not enable ::operator delete(void* ptr, std::size_t sz) by default for some reason
-				if constexpr(alignof(T) <= __STDCPP_DEFAULT_NEW_ALIGNMENT__){
-					::operator delete(p);
-				}else{
-					::operator delete(p, static_cast<std::align_val_t>(alignof(T)));
-				}
-			#else //__cpp_sized_deallocation
-			size_type bytes = has_overflow(n) ? std::numeric_limits<size_type>::max() : n*sizeof(T);
-				if constexpr(alignof(T) <= __STDCPP_DEFAULT_NEW_ALIGNMENT__){
-					::operator delete(p, bytes);
-				}else{
-					::operator delete(p, bytes, static_cast<std::align_val_t>(alignof(T)));
-				}
-			#endif //__cpp_sized_deallocation
-
-		}
-#endif //__cplusplus
-		constexpr size_type max_size(void)const{
-			return std::numeric_limits<size_type>::max()/sizeof(T);
-		}
-	};
 	template<class T, class U>
 	constexpr bool operator==(const allocator<T>&, const allocator<U>&){
 		return true;

include/rexy/compat/allocator.hpp

@@ -16,23 +16,8 @@
 	along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#ifndef REXY_CONCEPTS_ALLOCATOR_HPP
+#if __cplusplus >= 202002L
-#define REXY_CONCEPTS_ALLOCATOR_HPP
+	#include "cpp20/allocator.hpp"
-
+#else
-#include <concepts> //convertible_to
+	#include "cpp17/allocator.hpp"
-
-namespace rexy{
-
-	template<class T>
-	concept Allocator = requires(T a, typename T::size_type sz, typename T::pointer pa){
-		typename T::value_type;
-		typename T::size_type;
-		typename T::pointer;
-		typename T::const_pointer;
-		{a.allocate(sz)} -> std::convertible_to<typename T::pointer>;
-		{a.deallocate(pa, sz)};
-	};
-
-}
-
 #endif

include/rexy/compat/cpp17/allocator.hpp

@@ -0,0 +1,100 @@
+/**
+	This file is a part of rexy's general purpose library
+	Copyright (C) 2022 rexy712
+
+	This program is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef REXY_COMPAT_CPP17_DEFAULT_ALLOCATOR_HPP
+#define REXY_COMPAT_CPP17_DEFAULT_ALLOCATOR_HPP
+
+#include <cstddef> //ptrdiff_t, size_t
+#include <type_traits> //true_type, false_type
+#include <new>
+#include <limits> //numeric_limits
+
+#include "../../rexy.hpp"
+
+#define REXY_ALLOCATOR_CONCEPT class
+
+namespace rexy{
+
+	template<class T>
+	struct allocator
+	{
+		using pointer = T*;
+		using const_pointer = const T*;
+		using void_pointer = void*;
+		using const_void_pointer = const void*;
+		using value_type = T;
+		using size_type = std::size_t;
+		using difference_type = ptrdiff_t;
+		using is_always_equal = std::true_type;
+		using propagate_on_container_copy_assignment = std::false_type;
+		using propagate_on_container_move_assignment = std::false_type;
+		using propagate_on_container_swap = std::false_type;
+
+		template<class U>
+		struct rebind{
+			using other = allocator<U>;
+		};
+
+	private:
+		constexpr bool has_overflow(size_type n)const{
+			return n > max_size();
+		}
+
+	public:
+		allocator(void) = default;
+		allocator(const allocator&) = default;
+		allocator(allocator&&) = default;
+		template<class U>
+		constexpr allocator(const allocator<U>&)noexcept{}
+		~allocator(void) = default;
+
+		pointer allocate(size_type n){
+			size_type bytes = has_overflow(n) ? std::numeric_limits<size_type>::max() : n*sizeof(T);
+
+			if constexpr(alignof(T) <= __STDCPP_DEFAULT_NEW_ALIGNMENT__){
+				return reinterpret_cast<pointer>(::operator new(bytes));
+			}else{
+				return reinterpret_cast<pointer>(::operator new(bytes, static_cast<std::align_val_t>(alignof(T))));
+			}
+		}
+		void deallocate(pointer p, size_type n){
+			#if !defined(__cpp_sized_deallocation)
+				//clang does not enable ::operator delete(void* ptr, std::size_t sz) by default for some reason
+				if constexpr(alignof(T) <= __STDCPP_DEFAULT_NEW_ALIGNMENT__){
+					::operator delete(p);
+				}else{
+					::operator delete(p, static_cast<std::align_val_t>(alignof(T)));
+				}
+			#else //__cpp_sized_deallocation
+			size_type bytes = has_overflow(n) ? std::numeric_limits<size_type>::max() : n*sizeof(T);
+				if constexpr(alignof(T) <= __STDCPP_DEFAULT_NEW_ALIGNMENT__){
+					::operator delete(p, bytes);
+				}else{
+					::operator delete(p, bytes, static_cast<std::align_val_t>(alignof(T)));
+				}
+			#endif //__cpp_sized_deallocation
+
+		}
+		constexpr size_type max_size(void)const{
+			return std::numeric_limits<size_type>::max()/sizeof(T);
+		}
+	};
+
+}
+
+#endif

include/rexy/compat/cpp17/string_base.hpp

@@ -25,9 +25,17 @@
 #include <type_traits> //{false,true}_type, declval, enable_if, remove_reference, decay
 
 #include "../../utility.hpp" //strlen, strncmp
+#include "../../traits.hpp"
 
 namespace rexy{
 
+	template<class Left, class Right>
+	class string_cat_expr;
+	template<class Char, REXY_ALLOCATOR_CONCEPT Alloc>
+	class basic_string;
+	template<class Char>
+	class basic_string_view;
+
 	#define REXY_HAS_MEMFUN_WITH_RET(type, ret, fun, ...) \
 		template<class T> \
 		struct has_##fun##_f{ \
@@ -62,9 +70,35 @@ namespace rexy{
 	#undef REXY_HAS_MEMFUN_WITH_RET
 	#undef REXY_HAS_MEMOP_WITH_RET
 
+	template<class T>
+	struct is_basic_string{
+		template<class Char, class Alloc>
+		static std::true_type check(const basic_string<Char,Alloc>*);
+		static std::false_type check(...);
+
+		static constexpr bool value = decltype(check(std::declval<rexy::remove_cvref_t<T>*>()))::value;
+	};
+	template<class T>
+	struct is_basic_string_view{
+		template<class Char>
+		static std::true_type check(const basic_string_view<Char>*);
+		static std::false_type check(...);
+
+		static constexpr bool value = decltype(check(std::declval<rexy::remove_cvref_t<T>*>()))::value;
+	};
+	template<class T>
+	struct is_basic_string_expr{
+		template<class Left, class Right>
+		static std::true_type check(const string_cat_expr<Left,Right>*);
+		static std::false_type check(...);
+
+		static constexpr bool value = decltype(check(std::declval<rexy::remove_cvref_t<T>*>()))::value;
+	};
+
 	template<class T>
 	struct is_string{
-		static constexpr bool value = has_length_f_v<T> && has_c_str_f_v<T> && has_indexop_f_v<T> && has_begin_f_v<T> && has_end_f_v<T>;
+		static constexpr bool value = (is_basic_string<T>::value || is_basic_string_view<T>::value) &&
+		                              (has_length_f_v<T> && has_c_str_f_v<T> && has_indexop_f_v<T> && has_begin_f_v<T> && has_end_f_v<T>);
 	};
 	template<class T>
 	static constexpr bool is_string_v = is_string<T>::value;
@@ -77,7 +111,7 @@ namespace rexy{
 	static constexpr bool are_strings_v = are_strings<Ts...>::value;
 	template<class T>
 	struct is_string_expr{
-		static constexpr bool value = rexy::is_template_type<T,string_cat_expr>::value;
+		static constexpr bool value = is_basic_string_expr<T>::value;
 	};
 	template<class T>
 	static constexpr bool is_string_expr_v = is_string_expr<T>::value;

include/rexy/compat/cpp20/allocator.hpp

@@ -0,0 +1,139 @@
+/**
+	This file is a part of rexy's general purpose library
+	Copyright (C) 2022 rexy712
+
+	This program is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef REXY_COMPAT_CPP20_DEFAULT_ALLOCATOR_HPP
+#define REXY_COMPAT_CPP20_DEFAULT_ALLOCATOR_HPP
+
+#include <cstddef> //ptrdiff_t, size_t
+#include <type_traits> //true_type, false_type
+#include <new>
+#include <limits> //numeric_limits
+#include <memory> //allocator
+
+#ifdef __cpp_concepts
+
+	#include <concepts> //convertible_to
+	template<class T>
+	concept Allocator = requires(T a, typename T::size_type sz, typename T::pointer pa){
+		typename T::value_type;
+		typename T::size_type;
+		typename T::pointer;
+		typename T::const_pointer;
+		{a.allocate(sz)} -> std::convertible_to<typename T::pointer>;
+		{a.deallocate(pa, sz)};
+	};
+	#define REXY_ALLOCATOR_CONCEPT Allocator
+
+#else //__cpp_concepts
+
+	#define REXY_ALLOCATOR_CONCEPT class
+
+#endif // __cpp_concepts
+
+#include "../../rexy.hpp"
+#include "../if_consteval.hpp"
+
+namespace rexy{
+
+	template<class T>
+	struct allocator
+	{
+		using pointer = T*;
+		using const_pointer = const T*;
+		using void_pointer = void*;
+		using const_void_pointer = const void*;
+		using value_type = T;
+		using size_type = std::size_t;
+		using difference_type = std::ptrdiff_t;
+		using is_always_equal = std::true_type;
+		using propagate_on_container_copy_assignment = std::false_type;
+		using propagate_on_container_move_assignment = std::false_type;
+		using propagate_on_container_swap = std::false_type;
+
+		template<class U>
+		struct rebind{
+			using other = allocator<U>;
+		};
+
+	private:
+		constexpr bool has_overflow(size_type n)const{
+			return n > max_size();
+		}
+
+	public:
+		constexpr allocator(void) = default;
+		constexpr allocator(const allocator&) = default;
+		constexpr allocator(allocator&&) = default;
+		template<class U>
+		constexpr allocator(const allocator<U>&)noexcept{}
+		constexpr ~allocator(void) = default;
+
+		//'::operator new' is never a constexpr call as of C++23. However, 'std::allocator::allocate' *is* transiently constexpr as of C++20,
+		//even though it directly calls '::operator new' as is stated in the standard. Therefore, when evaluating this call with support for
+		//'if consteval', we can use the 'std::allocator::allocate' constexpr-ness when this is in a constant evaluation context.
+		constexpr pointer allocate(size_type n){
+			size_type bytes = has_overflow(n) ? std::numeric_limits<size_type>::max() : n*sizeof(T);
+
+			REXY_if_consteval{
+					std::allocator<value_type> a;
+					const size_type num_items = n / sizeof(value_type);
+					return a.allocate(num_items);
+				}else{
+					if constexpr(alignof(T) <= __STDCPP_DEFAULT_NEW_ALIGNMENT__){
+						return reinterpret_cast<pointer>(::operator new(bytes));
+					}else{
+						return reinterpret_cast<pointer>(::operator new(bytes, static_cast<std::align_val_t>(alignof(T))));
+					}
+				} //if consteval
+		}
+
+
+		constexpr void deallocate(pointer p, size_type n){
+			REXY_if_consteval{
+					std::allocator<value_type> a;
+					const size_type num_items = n / sizeof(value_type);
+					return a.deallocate(p, num_items);
+				}else{
+
+				#if !defined(__cpp_sized_deallocation)
+					//clang does not enable ::operator delete(void* ptr, std::size_t sz) by default for some reason
+					if constexpr(alignof(T) <= __STDCPP_DEFAULT_NEW_ALIGNMENT__){
+						::operator delete(p);
+					}else{
+						::operator delete(p, static_cast<std::align_val_t>(alignof(T)));
+					}
+				#else //__cpp_sized_deallocation
+					size_type bytes = has_overflow(n) ? std::numeric_limits<size_type>::max() : n*sizeof(T);
+					if constexpr(alignof(T) <= __STDCPP_DEFAULT_NEW_ALIGNMENT__){
+						::operator delete(p, bytes);
+					}else{
+						::operator delete(p, bytes, static_cast<std::align_val_t>(alignof(T)));
+					}
+				#endif //__cpp_sized_deallocation
+
+			} //if consteval
+
+		}
+		constexpr size_type max_size(void)const{
+			return std::numeric_limits<size_type>::max()/sizeof(T);
+		}
+	};
+
+}
+
+#endif

include/rexy/compat/cpp20/string_base.hpp

@@ -24,11 +24,71 @@
 #include <utility> //forward
 #include <type_traits> //decay, is_nothrow_assignable
 
-#include "../../concepts/string.hpp"
 #include "../../utility.hpp" //strlen, strncmp
 
 namespace rexy{
 
+	template<class Left, class Right>
+	class string_cat_expr;
+	template<class Char, REXY_ALLOCATOR_CONCEPT Alloc>
+	class basic_string;
+	template<class Char>
+	class basic_string_view;
+
+	template<class T>
+	struct is_basic_string{
+		template<class Char, class Alloc>
+		static std::true_type check(const basic_string<Char,Alloc>*);
+		static std::false_type check(...);
+
+		static constexpr bool value = decltype(check(std::declval<std::remove_cvref_t<T>*>()))::value;
+	};
+
+	template<class T>
+	struct is_basic_string_view{
+		template<class Char>
+		static std::true_type check(const basic_string_view<Char>*);
+		static std::false_type check(...);
+
+		static constexpr bool value = decltype(check(std::declval<std::remove_cvref_t<T>*>()))::value;
+	};
+
+	template<class T>
+	struct is_basic_string_expr{
+		template<class Left, class Right>
+		static std::true_type check(const string_cat_expr<Left,Right>*);
+		static std::false_type check(...);
+
+		static constexpr bool value = decltype(check(std::declval<std::remove_cvref_t<T>*>()))::value;
+	};
+
+	template<class T>
+	concept BasicString = requires(const T& a){
+		requires(is_basic_string<T>::value || is_basic_string_view<T>::value);
+		{std::as_const(a).length()} -> std::convertible_to<typename std::decay_t<T>::size_type>;
+		{std::as_const(a).c_str()} -> std::convertible_to<typename std::decay_t<T>::const_pointer>;
+		{std::as_const(a)[0]} -> std::convertible_to<typename std::decay_t<T>::const_reference>;
+		{std::as_const(a).begin()} -> std::convertible_to<typename std::decay_t<T>::const_iterator>;
+		{std::as_const(a).end()} -> std::convertible_to<typename std::decay_t<T>::const_iterator>;
+	};
+	template<class T>
+	concept StringExpr = is_basic_string_expr<T>::value;
+	template<class T>
+	concept String = BasicString<T> || StringExpr<T>;
+
+	template<class T>
+	struct is_string{
+		static constexpr bool value = BasicString<T>;
+	};
+	template<class T>
+	static constexpr bool is_string_v = is_string<T>::value;
+	template<class T>
+	struct is_string_expr{
+		static constexpr bool value = StringExpr<T>;
+	};
+	template<class T>
+	static constexpr bool is_string_expr_v = is_string_expr<T>::value;
+
 	//Compare
 	template<BasicString Str1, BasicString Str2>
 	constexpr bool operator==(Str1&& left, Str2&& right){

include/rexy/concepts/string.hpp

@@ -1,105 +0,0 @@
-/**
-	This file is a part of rexy's general purpose library
-	Copyright (C) 2022 rexy712
-
-	This program is free software: you can redistribute it and/or modify
-	it under the terms of the GNU General Public License as published by
-	the Free Software Foundation, either version 3 of the License, or
-	(at your option) any later version.
-
-	This program is distributed in the hope that it will be useful,
-	but WITHOUT ANY WARRANTY; without even the implied warranty of
-	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-	GNU General Public License for more details.
-
-	You should have received a copy of the GNU General Public License
-	along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-#ifndef REXY_CONCEPTS_STRING_HPP
-#define REXY_CONCEPTS_STRING_HPP
-
-#include <type_traits> //decay
-#include <concepts> //convertible_to
-#include <utility> //as_const
-
-#include "../traits.hpp"
-
-namespace rexy{
-
-	template<class Left, class Right>
-	class string_cat_expr;
-	template<class Char, REXY_ALLOCATOR_CONCEPT Alloc>
-	class basic_string;
-	template<class Char>
-	class basic_string_view;
-
-	template<class T>
-	struct is_basic_string{
-		template<class Char, class Alloc>
-		static std::true_type check(const basic_string<Char,Alloc>*);
-		static std::false_type check(...);
-
-		static constexpr bool value = decltype(check(std::declval<std::remove_cvref_t<T>*>()))::value;
-	};
-
-	template<class T>
-	struct is_basic_string_view{
-		template<class Char>
-		static std::true_type check(const basic_string_view<Char>*);
-		static std::false_type check(...);
-
-		static constexpr bool value = decltype(check(std::declval<std::remove_cvref_t<T>*>()))::value;
-	};
-
-	template<class T>
-	struct is_basic_string_expr{
-		template<class Left, class Right>
-		static std::true_type check(const string_cat_expr<Left,Right>*);
-		static std::false_type check(...);
-
-		static constexpr bool value = decltype(check(std::declval<std::remove_cvref_t<T>*>()))::value;
-	};
-
-	template<class T>
-	concept BasicString = requires(const T& a){
-		requires(is_basic_string<T>::value || is_basic_string_view<T>::value);
-		{std::as_const(a).length()} -> std::convertible_to<typename std::decay_t<T>::size_type>;
-		{std::as_const(a).c_str()} -> std::convertible_to<typename std::decay_t<T>::const_pointer>;
-		{std::as_const(a)[0]} -> std::convertible_to<typename std::decay_t<T>::const_reference>;
-		{std::as_const(a).begin()} -> std::convertible_to<typename std::decay_t<T>::const_iterator>;
-		{std::as_const(a).end()} -> std::convertible_to<typename std::decay_t<T>::const_iterator>;
-	};
-	template<class T>
-	concept StringExpr = is_basic_string_expr<T>::value;
-	template<class T>
-	concept String = BasicString<T> || StringExpr<T>;
-
-	template<class T>
-	struct is_string{
-		static constexpr bool value = BasicString<T>;
-	};
-	template<class T>
-	static constexpr bool is_string_v = is_string<T>::value;
-	template<class... Ts>
-	struct are_strings{
-		static constexpr bool value = (BasicString<Ts> && ...);
-	};
-	template<class... Ts>
-	static constexpr bool are_strings_v = are_strings<Ts...>::value;
-	template<class T>
-	struct is_string_expr{
-		static constexpr bool value = StringExpr<T>;
-	};
-	template<class T>
-	static constexpr bool is_string_expr_v = is_string_expr<T>::value;
-	template<class... Ts>
-	struct are_string_expr{
-		static constexpr bool value = (StringExpr<Ts> && ...);
-	};
-	template<class... Ts>
-	static constexpr bool are_string_expr_v = are_string_expr<Ts...>::value;
-
-}
-
-#endif