[Type] Convert is_vector trait to concept

Sofa/framework/Core/src/sofa/core/objectmodel/BaseContext.h

@@ -413,7 +413,7 @@ class BaseContext::GetObjectsCallBackT : public BaseContext::GetObjectsCallBack
     GetObjectsCallBackT(Container* d) : dest(d) {}
     void operator()(void* ptr) override
     {
-        if constexpr (sofa::type::trait::is_vector<Container>::value)
+        if constexpr (sofa::type::trait::is_vector<Container>)
         {
             dest->push_back(reinterpret_cast<T*>(ptr));
         }

Sofa/framework/Helper/src/sofa/helper/accessor/ReadAccessor.h

@@ -84,7 +84,7 @@ class ReadAccessor<FixedArrayLikeType, std::enable_if_t<sofa::type::trait::is_fi
 
 template<class VectorLikeType>
 class ReadAccessor<VectorLikeType,
-                   std::enable_if_t<sofa::type::trait::is_vector<VectorLikeType>::value> >
+                   std::enable_if_t<sofa::type::trait::is_vector<VectorLikeType>> >
     : public ReadAccessorVector< VectorLikeType >
 {
 public:

Sofa/framework/Helper/src/sofa/helper/accessor/WriteAccessor.h

@@ -95,7 +95,7 @@ class WriteAccessor<FixedArrayLikeType, std::enable_if_t<sofa::type::trait::is_f
 
 template<class VectorLikeType>
 class WriteAccessor<VectorLikeType,
-                    std::enable_if_t<sofa::type::trait::is_vector<VectorLikeType>::value>>
+                    std::enable_if_t<sofa::type::trait::is_vector<VectorLikeType>>>
     : public WriteAccessorVector< VectorLikeType >
 {
 public:

Sofa/framework/Helper/src/sofa/helper/accessor/WriteOnlyAccessor.h

@@ -41,7 +41,7 @@ class WriteOnlyAccessor : public WriteAccessor<T, Enable>
 
 template<class VectorLikeType>
 class WriteOnlyAccessor<VectorLikeType,
-                        std::enable_if_t<sofa::type::trait::is_vector<VectorLikeType>::value> >
+                        std::enable_if_t<sofa::type::trait::is_vector<VectorLikeType>> >
     : public WriteAccessorVector< VectorLikeType >
 {
 public:

Sofa/framework/LinearAlgebra/src/sofa/linearalgebra/CompressedRowSparseMatrixMechanical.h

@@ -1199,7 +1199,7 @@ class CompressedRowSparseMatrixMechanical final // final is used to allow the co
 
     /// equal result = this * v
     /// @warning The block sizes must be compatible ie v.size() must be a multiple of block size.
-    template< typename V1, typename V2, std::enable_if_t<sofa::type::trait::is_vector<V1>::value && sofa::type::trait::is_vector<V2>::value, int> = 0 >
+    template< typename V1, typename V2, std::enable_if_t<sofa::type::trait::is_vector<V1> && sofa::type::trait::is_vector<V2>, int> = 0 >
     void mul( V2& result, const V1& v ) const
     {
         this-> template tmul< Real, V2, V1 >(result, v);

Sofa/framework/Type/src/sofa/type/trait/is_vector.h

@@ -27,38 +27,16 @@ namespace sofa::type::trait
 
 /// Detect if a type T has iterator/const iterator function, operator[](size_t) and is dynamically resizable (resize function)
 template<typename T>
-struct is_vector
+concept is_vector = requires(std::remove_cv_t<T> t, const std::remove_cv_t<T> ct)
 {
-    typedef typename std::remove_const<T>::type test_type;
+    t.begin() -> T::iterator;
+    t.end() -> T::iterator;
 
-    template<typename A>
-    static constexpr bool test(
-        A * pt,
-        A const * cpt = nullptr,
-        decltype(pt->begin()) * = nullptr,
-        decltype(pt->end()) * = nullptr,
-        decltype(cpt->begin()) * = nullptr,
-        decltype(cpt->end()) * = nullptr,
-        typename std::decay<decltype((*pt)[0])>::type * = nullptr,   ///< Is there an operator[] ?
-        decltype(pt->resize(1)) * = nullptr,
-        typename A::iterator * = nullptr,
-        typename A::const_iterator * = nullptr,
-        typename A::value_type * = nullptr) {
+    ct.begin() -> T::const_iterator;
+    ct.end() -> T::const_iterator;
 
-        typedef typename A::iterator iterator;
-        typedef typename A::const_iterator const_iterator;
-        return  std::is_same<decltype(pt->begin()),iterator>::value
-                && std::is_same<decltype(pt->end()),iterator>::value
-                && std::is_same<decltype(cpt->begin()),const_iterator>::value
-                && std::is_same<decltype(cpt->end()),const_iterator>::value;
-    }
-
-    template<typename A>
-    static constexpr bool test(...) {
-        return false;
-    }
-
-    static const bool value = test<test_type>(nullptr);
+    t[0];
+    t.resize(1);
 };
 
 }