fig15_20.cpp was compiled error on VisualStudio 2022.

[jmchen-i8]

Hi there,

In my opinion, VS C++ does not fully qualify the iterator's type name due to I verify the below statement true. std::cout << std::is_base_of_v<std::random_access_iterator_tag, std::array<int, 5>::iterator::iterator_category>; // 1(True) I couldn't find any workaround yet. Any idea or suggestion will be welcome.

Regards.

-----snip----- Build started at 9:54 AM... 1>------ Build started: Project: cpp20_test, Configuration: Debug x64 ------ 1>Source.cpp 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(15,24): error C2923: 'std::is_base_of_v': 'std::_Array_const_iterator<_Ty,5>::iterator_category' is not a valid template type argument for parameter '_Derived' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(15,24): error C2923: with 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(15,24): error C2923: [ 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(15,24): error C2923: _Ty=int 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(15,24): error C2923: ] 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(16,19): 1>see declaration of 'std::_Array_const_iterator<_Ty,5>::iterator_category' 1> with 1> [ 1> _Ty=int 1> ] 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(15,24): 1>the template instantiation context (the oldest one first) is 1> C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(39,19): 1> see reference to function template instantiation 'auto customDistance<std::_Array_const_iterator<_Ty,5>>(Iterator,Iterator)' being compiled 1> with 1> [ 1> _Ty=int, 1> Iterator=std::_Array_const_iterator<int,5> 1> ] 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(16,19): error C2275: 'std::_Array_const_iterator<_Ty,5>::iterator_category': expected an expression instead of a type 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(16,19): error C2275: with 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(16,19): error C2275: [ 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(16,19): error C2275: _Ty=int 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(16,19): error C2275: ] 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(16,37): error C2059: syntax error: ')' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(16,39): error C2143: syntax error: missing ';' before '{' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(13,51): error C2181: illegal else without matching if 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(15,24): error C2923: 'std::is_base_of_v': 'std::_List_const_iterator<std::_List_val<std::_List_simple_types<_Ty>>>::iterator_category' is not a valid template type argument for parameter '_Derived' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(15,24): error C2923: with 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(15,24): error C2923: [ 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(15,24): error C2923: _Ty=int 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(15,24): error C2923: ] 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(16,19): 1>see declaration of 'std::_List_const_iterator<std::_List_val<std::_List_simple_types<_Ty>>>::iterator_category' 1> with 1> [ 1> _Ty=int 1> ] 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(15,24): 1>the template instantiation context (the oldest one first) is 1> C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(41,19): 1> see reference to function template instantiation 'auto customDistance<std::_List_const_iterator<std::_List_val<std::_List_simple_types<_Ty>>>>(Iterator,Iterator)' being compiled 1> with 1> [ 1> _Ty=int, 1> Iterator=std::_List_const_iterator<std::_List_val<std::_List_simple_types>> 1> ] 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(16,19): error C2275: 'std::_List_const_iterator<std::_List_val<std::_List_simple_types<_Ty>>>::iterator_category': expected an expression instead of a type 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(16,19): error C2275: with 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(16,19): error C2275: [ 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(16,19): error C2275: _Ty=int 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(16,19): error C2275: ] 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(18,20): error C2676: binary '-': 'Iterator' does not define this operator or a conversion to a type acceptable to the predefined operator 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(18,20): error C2676: with 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(18,20): error C2676: [ 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(18,20): error C2676: Iterator=std::_List_const_iterator<std::_List_val<std::_List_simple_types>> 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(18,20): error C2676: ] 1>C:\Program Files\Microsoft Visual Studio\2022\Enterprise\VC\Tools\MSVC\14.38.33130\include\xutility(1775,5): 1>could be 'unknown-type std::operator -(const std::reverse_iterator<_BidIt> &,const std::reverse_iterator<_BidIt2> &) noexcept()' 1> C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(18,16): 1> 'unknown-type std::operator -(const std::reverse_iterator<_BidIt> &,const std::reverse_iterator<_BidIt2> &) noexcept()': could not deduce template argument for 'const std::reverse_iterator<_BidIt> &' from 'Iterator' 1> with 1> [ 1> Iterator=std::_List_const_iterator<std::_List_val<std::_List_simple_types>> 1> ] 1>C:\Program Files\Microsoft Visual Studio\2022\Enterprise\VC\Tools\MSVC\14.38.33130\include\xutility(4326,30): 1>or 'unknown-type std::operator -(const std::move_iterator<_Iter> &,const std::move_iterator<_Iter2> &) noexcept()' 1> C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(18,16): 1> 'unknown-type std::operator -(const std::move_iterator<_Iter> &,const std::move_iterator<_Iter2> &) noexcept()': could not deduce template argument for 'const std::move_iterator<_Iter> &' from 'Iterator' 1> with 1> [ 1> Iterator=std::_List_const_iterator<std::_List_val<std::_List_simple_types>> 1> ] 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(20,5): error C2059: syntax error: 'else' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(26,9): error C2059: syntax error: 'for' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(13,51): error C2143: syntax error: missing ')' before ';' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(26,39): error C2143: syntax error: missing ';' before '!=' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(13,51): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(26,47): error C2059: syntax error: '++' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(26,53): error C2059: syntax error: ')' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(28,9): error C2059: syntax error: '}' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(31,5): error C2059: syntax error: '}' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(41,62): error C2143: syntax error: missing ';' before '}' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(41,62): error C2059: syntax error: '}' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(42,15): error C2143: syntax error: missing ';' before '<<' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(42,15): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(42,10): error C2371: 'std::cout': redefinition; different basic types 1>C:\Program Files\Microsoft Visual Studio\2022\Enterprise\VC\Tools\MSVC\14.38.33130\include\iostream(39,75): 1>see declaration of 'std::cout' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(43,1): error C2059: syntax error: '}' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(43,1): error C2143: syntax error: missing ';' before '}' 1>C:\Users\jmche\source\repos\Project1\cpp20_test\Source.cpp(60,1): error C1903: unable to recover from previous error(s); stopping compilation 1>Done building project "cpp20_test.vcxproj" -- FAILED. ========== Build: 0 succeeded, 1 failed, 69 up-to-date, 0 skipped ========== ========== Build completed at 9:54 AM and took 08.896 seconds ==========