From dff330373333b7be8a6468708c291c7cdb252d6d Mon Sep 17 00:00:00 2001
From: rexy712 <rexy712@protonmail.com>
Date: Wed, 20 Jul 2022 13:31:11 -0700
Subject: [PATCH] Add string comparisons

---
 include/rexy/compat/cpp17/string_base.hpp | 47 +++++++++++++++--------
 include/rexy/compat/cpp20/string_base.hpp | 36 +++++++++--------
 2 files changed, 53 insertions(+), 30 deletions(-)

diff --git a/include/rexy/compat/cpp17/string_base.hpp b/include/rexy/compat/cpp17/string_base.hpp
index ffced5e..8c39dac 100644
--- a/include/rexy/compat/cpp17/string_base.hpp
+++ b/include/rexy/compat/cpp17/string_base.hpp
@@ -23,6 +23,7 @@
 
 #include <utility> //forward
 #include <type_traits> //{false,true}_type, declval, enable_if, remove_reference, decay
+#include <algorithm> //lexicographically_compare
 
 #include "../../utility.hpp" //strlen, strncmp
 #include "../../traits.hpp"
@@ -124,45 +125,61 @@ namespace rexy{
 
 	//Compare
 	template<class Str1, class Str2, std::enable_if_t<are_strings<Str1, Str2>::value,int> = 0>
-	constexpr bool operator==(Str1&& left, Str2&& right){
+	constexpr bool operator==(const Str1& left, const Str2& right){
 		if(left.length() != right.length()){
 			return false;
 		}
 		return !rexy::strncmp(left.c_str(), right.c_str(), left.length()+1);
 	}
 	template<class Str1, std::enable_if_t<are_strings<Str1>::value,int> = 0>
-	constexpr bool operator==(Str1&& left, typename std::decay_t<Str1>::const_pointer right){
+	constexpr bool operator==(const Str1& left, typename std::decay_t<Str1>::const_pointer right){
 		if(right == nullptr){
 			return false;
 		}
-		const auto rlen = rexy::strlen(right);
-		if(rlen != left.length()){
+		const rexy::basic_string_view rstr(right);
+		if(rstr.length() != left.length()){
 			return false;
 		}
-		return !rexy::strncmp(left.c_str(), right, rlen+1);
+		return !rexy::strncmp(left.c_str(), rstr.c_str(), left.length());
 	}
 	template<class Str1, std::enable_if_t<are_strings<Str1>::value,int> = 0>
-	constexpr bool operator==(typename std::decay_t<Str1>::const_pointer left, Str1&& right){
+	constexpr bool operator==(typename std::decay_t<Str1>::const_pointer left, const Str1& right){
 		if(left == nullptr){
 			return false;
 		}
-		const auto llen = rexy::strlen(left);
-		if(llen != right.length()){
+		const rexy::basic_string_view lstr(left);
+		if(lstr.length() != right.length()){
 			return false;
 		}
-		return !rexy::strncmp(left, right.c_str(), llen+1);
+		return !rexy::strncmp(lstr.c_str(), right.c_str(), right.length());
 	}
 	template<class Str1, class Str2, std::enable_if_t<are_strings<Str1, Str2>::value,int> = 0>
-	constexpr bool operator!=(Str1&& left, Str2&& right)noexcept{
-		return !(std::forward<Str1>(left) == std::forward<Str2>(right));
+	constexpr bool operator!=(const Str1& left, const Str2& right)noexcept{
+		return !(left == right);
 	}
 	template<class Str1, std::enable_if_t<are_strings<Str1>::value,int> = 0>
-	constexpr bool operator!=(Str1&& left, typename std::decay_t<Str1>::const_pointer right)noexcept{
-		return !(std::forward<Str1>(left) == right);
+	constexpr bool operator!=(const Str1& left, typename std::decay_t<Str1>::const_pointer right)noexcept{
+		return !(left == right);
 	}
 	template<class Str1, std::enable_if_t<are_strings<Str1>::value,int> = 0>
-	constexpr bool operator!=(typename std::decay_t<Str1>::const_pointer left, Str1&& right)noexcept{
-		return !(left == std::forward<Str1>(right));
+	constexpr bool operator!=(typename std::decay_t<Str1>::const_pointer left, const Str1& right)noexcept{
+		return !(left == right);
+	}
+	template<class Str1, class Str2, std::enable_if_t<are_string<Str1,Str2>::value,int> = 0>
+	constexpr bool operator<(const Str1& left, const Str2& right)noexcept{
+		return std::lexicographical_compare(left.begin(), left.end(), right.begin(), right.end());
+	}
+	template<class Str1, class Str2, std::enable_if_t<are_string<Str1,Str2>::value,int> = 0>
+	constexpr bool operator<=(const Str1& left, const Str2& right)noexcept{
+		return !(right < left);
+	}
+	template<class Str1, class Str2, std::enable_if_t<are_string<Str1,Str2>::value,int> = 0>
+	constexpr bool operator>(const Str1& left, const Str2& right)noexcept{
+		return (right < left);
+	}
+	template<class Str1, class Str2, std::enable_if_t<are_string<Str1,Str2>::value,int> = 0>
+	constexpr bool operator>=(const Str1& left, const Str2& right)noexcept{
+		return !(left < right);
 	}
 
 	//String + string concat
diff --git a/include/rexy/compat/cpp20/string_base.hpp b/include/rexy/compat/cpp20/string_base.hpp
index 9745cf4..196380a 100644
--- a/include/rexy/compat/cpp20/string_base.hpp
+++ b/include/rexy/compat/cpp20/string_base.hpp
@@ -23,6 +23,7 @@
 
 #include <utility> //forward
 #include <type_traits> //decay, is_nothrow_assignable
+#include <algorithm> //lexicographically_compare_three_way
 
 #include "../../utility.hpp" //strlen, strncmp
 
@@ -91,45 +92,50 @@ namespace rexy{
 
 	//Compare
 	template<BasicString Str1, BasicString Str2>
-	constexpr bool operator==(Str1&& left, Str2&& right){
+	constexpr bool operator==(const Str1& left, const Str2& right){
 		if(left.length() != right.length()){
 			return false;
 		}
 		return !rexy::strncmp(left.c_str(), right.c_str(), left.length()+1);
 	}
 	template<BasicString Str1>
-	constexpr bool operator==(Str1&& left, typename std::decay_t<Str1>::const_pointer right){
+	constexpr bool operator==(const Str1& left, typename std::decay_t<Str1>::const_pointer right)noexcept{
 		if(right == nullptr){
 			return false;
 		}
-		const auto rlen = rexy::strlen(right);
-		if(rlen != left.length()){
+		const rexy::basic_string_view rstr(right);
+		if(rstr.length() != left.length()){
 			return false;
 		}
-		return !rexy::strncmp(left.c_str(), right, rlen+1);
+		return !rexy::strncmp(left.c_str(), rstr.c_str(), left.length());
 	}
 	template<BasicString Str1>
-	constexpr bool operator==(typename std::decay_t<Str1>::const_pointer left, Str1&& right){
+	constexpr bool operator==(typename std::decay_t<Str1>::const_pointer left, const Str1& right)noexcept{
 		if(left == nullptr){
 			return false;
 		}
-		const auto llen = rexy::strlen(left);
-		if(llen != right.length()){
+		const rexy::basic_string_view lstr(left);
+		if(lstr.length() != right.length()){
 			return false;
 		}
-		return !rexy::strncmp(left, right.c_str(), llen+1);
+		return !rexy::strncmp(lstr.c_str(), right.c_str(), right.length());
 	}
 	template<BasicString Str1, BasicString Str2>
-	constexpr bool operator!=(Str1&& left, Str2&& right){
-		return !(std::forward<Str1>(left) == std::forward<Str2>(right));
+	constexpr bool operator!=(const Str1& left, const Str2& right)noexcept{
+		return !(left == right);
 	}
 	template<BasicString Str1>
-	constexpr bool operator!=(Str1&& left, typename std::decay_t<Str1>::const_pointer right){
-		return !(std::forward<Str1>(left) == right);
+	constexpr bool operator!=(const Str1& left, typename std::decay_t<Str1>::const_pointer right)noexcept{
+		return !(left == right);
 	}
 	template<BasicString Str1>
-	constexpr bool operator!=(typename std::decay_t<Str1>::const_pointer left, Str1&& right){
-		return !(left == std::forward<Str1>(right));
+	constexpr bool operator!=(typename std::decay_t<Str1>::const_pointer left, const Str1& right)noexcept{
+		return !(left == right);
+	}
+
+	template<BasicString Str1, BasicString Str2>
+	constexpr auto operator<=>(const Str1& left, const Str2& right)noexcept{
+		return std::lexicographical_compare_three_way(left.begin(), left.end(), right.begin(), right.end());
 	}
 
 	//String + string concat