lalittech
diff --git a/‎.github/workflows/ci.yml
+5-5 b/‎.github/workflows/ci.yml
+5-5
diff --git a/‎01.01-variadicTemplateSum0/main.cpp
-18 b/‎01.01-variadicTemplateSum0/main.cpp
-18
diff --git a/‎01.01-variadicTemplateSum0/CMakeLists.txt renamed to ‎01.01-variadicTemplateSum2/CMakeLists.txt b/‎01.01-variadicTemplateSum0/CMakeLists.txt renamed to ‎01.01-variadicTemplateSum2/CMakeLists.txt
diff --git a/‎01.01-variadicTemplateSum2/main.cpp
+38 b/‎01.01-variadicTemplateSum2/main.cpp
+38
diff --git a/‎01.07-variableTemplate0/CMakeLists.txt renamed to ‎01.02-variableTemplate0/CMakeLists.txt b/‎01.07-variableTemplate0/CMakeLists.txt renamed to ‎01.02-variableTemplate0/CMakeLists.txt
diff --git a/‎01.07-variableTemplate0/main.cpp renamed to ‎01.02-variableTemplate0/main.cpp b/‎01.07-variableTemplate0/main.cpp renamed to ‎01.02-variableTemplate0/main.cpp
diff --git a/‎01.02-variadicTemplateSum1/main.cpp
-24 b/‎01.02-variadicTemplateSum1/main.cpp
-24
diff --git a/‎01.04-see-01.03-variadicTemplateSum2 renamed to ‎01.03-see-01.02-variableTemplate0 b/‎01.04-see-01.03-variadicTemplateSum2 renamed to ‎01.03-see-01.02-variableTemplate0
diff --git a/‎01.03-variadicTemplateSum2/main.cpp
-28 b/‎01.03-variadicTemplateSum2/main.cpp
-28
diff --git a/‎01.06-see-01.05-theSimplestConcept0 renamed to ‎01.04-see-01.01-variadicTemplateSum2 b/‎01.06-see-01.05-theSimplestConcept0 renamed to ‎01.04-see-01.01-variadicTemplateSum2
diff --git a/‎01.05-theSimplestConcept0/main.cpp
-23 b/‎01.05-theSimplestConcept0/main.cpp
-23
diff --git a/‎01.05-theSimplestConcept0/CMakeLists.txt renamed to ‎01.05-variadicTemplateSum3/CMakeLists.txt b/‎01.05-theSimplestConcept0/CMakeLists.txt renamed to ‎01.05-variadicTemplateSum3/CMakeLists.txt
diff --git a/‎01.05-variadicTemplateSum3/main.cpp
+26 b/‎01.05-variadicTemplateSum3/main.cpp
+26
diff --git a/‎01.09-byteLikeTypeConcept0/CMakeLists.txt renamed to ‎01.06-simpleRequirement0/CMakeLists.txt b/‎01.09-byteLikeTypeConcept0/CMakeLists.txt renamed to ‎01.06-simpleRequirement0/CMakeLists.txt
diff --git a/‎01.12-simpleRequirement0/main.cpp renamed to ‎01.06-simpleRequirement0/main.cpp
+2-2 b/‎01.12-simpleRequirement0/main.cpp renamed to ‎01.06-simpleRequirement0/main.cpp
+2-2
diff --git a/‎01.11-variadicTemplateSum3/CMakeLists.txt renamed to ‎01.07-nestedRequirement0/CMakeLists.txt b/‎01.11-variadicTemplateSum3/CMakeLists.txt renamed to ‎01.07-nestedRequirement0/CMakeLists.txt
diff --git a/‎01.13-nestedRequirement0/main.cpp renamed to ‎01.07-nestedRequirement0/main.cpp
+4-4 b/‎01.13-nestedRequirement0/main.cpp renamed to ‎01.07-nestedRequirement0/main.cpp
+4-4
diff --git a/‎01.12-simpleRequirement0/CMakeLists.txt renamed to ‎01.08-compoundRequirement0/CMakeLists.txt b/‎01.12-simpleRequirement0/CMakeLists.txt renamed to ‎01.08-compoundRequirement0/CMakeLists.txt
diff --git a/‎01.14-compoundRequirement0/main.cpp renamed to ‎01.08-compoundRequirement0/main.cpp
+7-6 b/‎01.14-compoundRequirement0/main.cpp renamed to ‎01.08-compoundRequirement0/main.cpp
+7-6
diff --git a/‎01.09-byteLikeTypeConcept0/main.cpp
-48 b/‎01.09-byteLikeTypeConcept0/main.cpp
-48
diff --git a/‎01.13-nestedRequirement0/CMakeLists.txt renamed to ‎01.09-typeRequirement0/CMakeLists.txt b/‎01.13-nestedRequirement0/CMakeLists.txt renamed to ‎01.09-typeRequirement0/CMakeLists.txt
diff --git a/‎01.09-typeRequirement0/main.cpp
+23 b/‎01.09-typeRequirement0/main.cpp
+23
diff --git a/‎01.14-compoundRequirement0/CMakeLists.txt renamed to ‎01.10-compoundRequirement1/CMakeLists.txt b/‎01.14-compoundRequirement0/CMakeLists.txt renamed to ‎01.10-compoundRequirement1/CMakeLists.txt
@@ -24,13 +24,13 @@ jobs:
             gcc_version: 11,
           }
 
-        # Clang-12
+        # Clang-13
         - {
-            name: "Linux Clang 12",
+            name: "Linux Clang 13",
             os: ubuntu-20.04,
             build_type: Release,
-            cxx: "clang++-12",
-            clang_version: 12,
+            cxx: "clang++-13",
+            clang_version: 13,
             libcxx: true
           }
 
@@ -98,7 +98,7 @@ jobs:
           )
         endif()
 
-    - name: Install Clang 12
+    - name: Install Clang 13
       id: install_clang_11
       if: startsWith(matrix.config.os, 'ubuntu') && startsWith(matrix.config.cxx, 'clang++-')
       shell: bash
 
@@ -0,0 +1,38 @@
+// Copyright (c) Andreas Fertig.
+// SPDX-License-Identifier: MIT
+
+#include <cstdio>
+#include <type_traits>
+
+template<typename T, typename... Ts>
+constexpr inline bool are_same_v =
+  std::conjunction_v<std::is_same<T, Ts>...>;
+
+template<typename T, typename...>
+struct first_arg {
+  using type = T;
+};
+
+template<typename... Args>
+using first_arg_t = typename first_arg<Args...>::type;
+
+template<typename... Args>
+std::enable_if_t<are_same_v<Args...>, first_arg_t<Args...>>
+Add(const Args&... args) noexcept
+{
+  return (... + args);
+}
+
+#ifdef WILL_NOT_COMPILE
+void WillNotCompile()
+{
+  printf("%d\n", Add(2, 3, 4.0));
+}
+#endif
+
+int main()
+{
+  printf("%d\n", Add(2, 3, 4));
+
+  printf("%d\n", Add(2));
+}
@@ -0,0 +1,26 @@
+// Copyright (c) Andreas Fertig.
+// SPDX-License-Identifier: MIT
+
+#include <cstdio>
+#include <type_traits>
+
+template<typename T, typename... Ts>
+constexpr bool are_same_v =
+  std::conjunction_v<std::is_same<T, Ts>...>;
+
+template<typename... Args> 
+// #A Requires-clause using are_same_v to ensure all Args are of the same type.
+requires are_same_v<Args...> 
+auto Add(Args&&... args) noexcept
+{
+  return (... + args);
+}
+
+
+
+int main()
+{
+  printf("%d\n", Add(2, 3, 4));
+
+  printf("%d\n", Add(2));
+}
@@ -5,14 +5,14 @@
 #include <type_traits>
 
 template<typename T, typename... Ts>
-inline constexpr bool are_same_v = std::conjunction_v<std::is_same<T, Ts>...>;
+constexpr bool are_same_v = std::conjunction_v<std::is_same<T, Ts>...>;
 
 template<typename... Args>
 requires
 
   requires(Args... args)
 {
-  (... + args);  // #A Check that args provides +
+  (... + args);  // #C SR: args  provides +
 }
 
 auto add(const Args&... args)
 
@@ -5,16 +5,16 @@
 #include <type_traits>
 
 template<typename T, typename... Ts>
-inline constexpr bool are_same_v = std::conjunction_v<std::is_same<T, Ts>...>;
+constexpr bool are_same_v = std::conjunction_v<std::is_same<T, Ts>...>;
 
 template<typename... Args>
 requires
 
 requires(Args... args)
 {
-  (... + args);                  // #A Check that args provides +
-  requires are_same_v<Args...>;  // #B Check all types are the same
-  requires sizeof...(Args) > 1;  // #C Check that the pack contains at least two elements
+  (... + args);                  // #C SR: args provides +
+  requires are_same_v<Args...>;  // #A NR: All types are the same
+  requires sizeof...(Args) > 1;  // #B NR: Pack contains at least two elements
 }
 
 
 
@@ -9,7 +9,7 @@ concept same_as =
   std::is_same_v<std::remove_cvref_t<T>, std::remove_cvref_t<U>>;
 
 template<typename T, typename... Ts>
-inline constexpr bool are_same_v = std::conjunction_v<std::is_same<T, Ts>...>;
+constexpr bool are_same_v = std::conjunction_v<std::is_same<T, Ts>...>;
 
 template<typename T, typename...>
 struct first_arg {
@@ -23,12 +23,13 @@ template<typename... Args>
 requires 
 requires(Args... args)
 {
-  (... + args);                  // #A Check that arg provides +
-  requires are_same_v<Args...>;  // #B Check all types are the same
-  requires sizeof...(Args) > 1;  // #C Check that the pack contains at least two elements
-
-  // #D Assert that ...+arg is noexcept and the return type is the same as the first argument type
+  (... + args);                  // #C SR: args provides +
+  requires are_same_v<Args...>;  // #A NR: All types are the same
+  requires sizeof...(Args) > 1;  // #B NR: Pack contains at least two elements
 
+  // #D // #E CR: ...+args is noexcept and the return type is the same as the first argument type
+  // { (... + args) } noexcept;
+  // { (... + args) } -> same_as<first_arg_t<Args...>>;
   { (... + args) } noexcept -> same_as<first_arg_t<Args...>>;
 }
 
 
@@ -0,0 +1,23 @@
+// Copyright (c) Andreas Fertig.
+// SPDX-License-Identifier: MIT
+
+#include <array>
+#include <vector>
+
+template<typename T>
+concept containerTypes = requires(T t)
+{  // #A Testing for various types in T
+  typename T::value_type;
+  typename T::size_type;
+  typename T::allocator_type;
+  typename T::iterator;
+  typename T::const_iterator;
+};
+
+struct A {};
+
+static_assert(not containerTypes<A>);
+static_assert(containerTypes<std::vector<int>>);
+
+static_assert(not containerTypes<std::array<int, 5>>);
+int main() {}
Original file line number	Diff line number	Diff line change
`@@ -5,14 +5,14 @@`
`5`	`5`	`#include <type_traits>`
`6`	`6`
`7`	`7`	`template<typename T, typename... Ts>`
`8`		`-inline constexpr bool are_same_v = std::conjunction_v<std::is_same<T, Ts>...>;`
	`8`	`+constexpr bool are_same_v = std::conjunction_v<std::is_same<T, Ts>...>;`
`9`	`9`
`10`	`10`	`template<typename... Args>`
`11`	`11`	`requires`
`12`	`12`
`13`	`13`	`requires(Args... args)`
`14`	`14`	`{`
`15`		`- (... + args); // #A Check that args provides +`
	`15`	`+ (... + args); // #C SR: args provides +`
`16`	`16`	`}`
`17`	`17`
`18`	`18`	`auto add(const Args&... args)`