// 1 filename:cpp2011-3-4-1.cpp // ver 0.1 June.12, 2014 // // 2 original examples and/or notes: // (c) ISO/IEC JTC1 SC22 WG21 N3242, April 12, 2011 // http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3242.pdf // 3 Basic concepts.3.4 Name lookup 3.4.1 Unqualified name lookup // 3 compile and output mechanism: // (c) Dr. OGAWA Kiyoshi, kaizen at gifu-u.ac.jp, // // 4 compile errors and/or warnings: // 4.1(c) Apple LLVM version 5.1 (clang-503.0.40) (based on LLVM 3.4svn) // Target: x86_64-apple-darwin13.2.0, Thread model: posix // Command/Options: c++ -std=c++11 -stdlib=libc++ -Wall cpp2011-3-4-1.cpp // (c) LLVM 2003-2009 University of Illinois at Urbana-Champaign. // 4.2. g++-4.9 (GCC) 4.9.0 20131229 (experimental) // Copyright (C) 2013 Free Software Foundation, Inc. // This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. // http://gcc.gnu.org/onlinedocs/gcc/Standards.html // Command/Options: g++-4.9 -std=c++11 -Wall cpp2011-3-4-1.cpp // g++-4.9: error: unrecognized command line option '-stdlib=libc++' // Configuration:brew install gcc49 // // 4.3. Visual Studio Express 2013, // (c) Microsoft http://www.visualstudio.com/ // SPEC: // Windows 7, .NET Framework // (c) VMware, Inc. // VMWare fusion 6 // // 5. Hardware: MacBook Pro, //(c) Intel http://ark.intel.com/products/37006/ //Core 2 Duo 2.53GHz, 8GB, 1067MHz DDR3 // // 6. Special Thanks: Upper organizatios and // ITSCJ/IPSJ http://www.itscj.ipsj.or.jp/itscj_english/index.html // NPO SESSAME project, http://www.sessame.jp/workinggroup/WorkingGroup3/ // Toyo Corporation, http://www.toyo.co.jp/English/ // Japan Standard Association, http://bit.ly/1lzykg1 // NPO TOPPERS project, https://www.toppers.jp/asp-d-download.html // Daido Universcity, http://www.daido-it.ac.jp/gakubugakka/computer/index.html // WITZ Co.Ltd., http://www.witz-inc.co.jp/products/solution/solution.html // SevenWise.co., http://www.7ws.co.jp/index.html // TOYOTA Motor Corporation, http://toyota.jp/ // IT planning Inc., http://www.itpl.co.jp/en/index.html // DENSO Corporation, http://www.globaldenso.com/en/ // Aisin Seiki co. Ltd., http://www.aisin.com/ // Spancion Inc., http://www.spansion.com/ // Yazaki Corporation, http://www.yazaki-group.com/global/ // Pananosic Corporation, http://www.panasonic.net/ // SWEST: Summer Workshop on Embedded System Technologies , http://swest.toppers.jp // CEST: Consortium for Embedded System Technology, http://www.ertl.jp/CEST/ // JUSE: Union of Japanese Scientists and Engineers, http://www.juse.or.jp/e/ // OSC:Open Source Conference, http://www.ospn.jp/ #include //#include //#include using namespace std; namespace N { int i = 4; extern int j; } typedef int f; namespace N { struct A { friend void f(A &); operator int(); void g(A a) { int i = f(a); // f is the typedef, not the friend // function: equivalent to int(a) } }; } namespace A { namespace N { void f(); } } void A::N::f() { ::N::i = 5; //cpp2011-3-4-1.cpp:81:1: error: use of undeclared identifier 'i' // The following scopes are searched for a declaration of i: // 1) outermost block scope of A::N::f, before the use of i // 2) scope of namespace N // 3) scope of namespace A // 4) global scope, before the definition of A::N::f } namespace M { class B { }; } namespace N { class Y : public M::B { class X { int a[i]; }; }; } // The following scopes are searched for a declaration of i: // 1) scope of class N::Y::X, before the use of i // 2) scope of class N::Y, before the definition of N::Y::X // 3) scope of N::Y’s base class M::B // 4) scope of namespace N, before the definition of N::Y // 5) global scope, before the definition of N class B { }; namespace M { namespace N { class X : public B { void f(); }; } } void M::N::X::f() { ::N::i = 16; } // The following scopes are searched for a declaration of i: // 1) outermost block scope of M::N::X::f, before the use of i // 2) scope of class M::N::X // 3) scope of M::N::X’s base class B // 4) scope of namespace M::N // 5) scope of namespace M // 6) global scope, before the definition of M::N::X::f struct A2 { typedef int AT; void f1(AT); void f2(float); template void f3(); }; struct B2 { typedef char AT; typedef float BT; friend void A2::f1(AT); // parameter type is A::AT friend void A2::f2(BT); // parameter type is B::BT friend void A2::f3(); // template argument is B::AT }; int main() { int i = 2; int N::j = i; // N::j == 4 cout << std::endl; return 0; } // 1 error // 1.1 LLVM >c++ -std=c++11 -stdlib=libc++ -Wall cpp2011-3-4-1.cpp //cpp2011-3-4-1.cpp:76:5: warning: unused variable 'i' [-Wunused-variable] //int i = f(a); // f is the typedef, not the friend // ^ //cpp2011-3-4-1.cpp:101:5: error: fields must have a constant size: 'variable length array in structure' extension will never be supported //int a[i]; // ^ //cpp2011-3-4-1.cpp:148:8: error: definition or redeclaration of 'j' not allowed inside a function //int N::j = i; // N::j == 4 // ~~~^ //cpp2011-3-4-1.cpp:101:5: warning: private field 'a' is not used [-Wunused-private-field] //int a[i]; // ^ //2 warnings and 2 errors generated. // 1.2 gcc > g++-4.9 -std=c++11 -Wall cpp2011-3-4-1.cpp //cpp2011-3-4-1.cpp: In member function 'void N::A::g(N::A)': //cpp2011-3-4-1.cpp:76:5: warning: unused variable 'i' [-Wunused-variable] // int i = f(a); // f is the typedef, not the friend // ^ //cpp2011-3-4-1.cpp: At global scope: //cpp2011-3-4-1.cpp:101:8: error: array bound is not an integer constant before ']' token // int a[i]; // ^ //cpp2011-3-4-1.cpp: In function 'int main()': //cpp2011-3-4-1.cpp:148:10: error: qualified-id in declaration before '=' token // int N::j = i; // N::j == 4 // ^ //cpp2011-3-4-1.cpp:148:10: error: invalid use of qualified-name 'N::j'