// N4606 Committee Draft, Standard for Programming Language C++
// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/n4606.pdf 
#define msg "p287.cpp(139)12.3.2 Conversion functions [class.conv.fct]"
// Edited by Dr. Ogawa Kiyoshi. Compile procedure and results record.

#include <iostream>

struct X {
operator int();
};
void f(X a) {
int i = int(a);
i = (int)a;
i = a;
}

class Y { };
struct Z {
explicit operator Y() const;
};
void h(Z z) {
Y y1(z); // OK: direct-initialization
Y y2 = z; // ill-formed: copy-initialization
Y y3 = (Y)z; // OK: cast notation
}
void g(X a, X b) {
int i = (a) ? 1+a : 0;
int j = (a&&b) ? a+b : i;
if (a) {
}
}

&ac.operator int*i; // syntax error:
// parsed as: &(ac.operator int *)i
// not as: &(ac.operator int)*i

operator int [[noreturn]] (); // error: noreturn attribute applied to a type


int main(){
  std::cout<< msg << std::endl;
  return EXIT_SUCCESS;
}

$ ./cppgl17.sh p289
$ clang++ p289.cpp
p289.cpp:23:3: error: no viable conversion from 'Z' to 'Y'
Y y2 = z; // ill-formed: copy-initialization
  ^    ~
p289.cpp:17:7: note: candidate constructor (the implicit copy constructor) not viable: no known conversion from 'Z' to 'const Y &' for 1st
      argument
class Y { };
      ^
p289.cpp:17:7: note: candidate constructor (the implicit move constructor) not viable: no known conversion from 'Z' to 'Y &&' for 1st
      argument
class Y { };
      ^
p289.cpp:33:2: error: C++ requires a type specifier for all declarations
&ac.operator int*i; // syntax error:
 ^
p289.cpp:33:2: error: declaration of reference variable 'ac' requires an initializer
&ac.operator int*i; // syntax error:
 ^~
p289.cpp:33:4: error: expected ';' after top level declarator
&ac.operator int*i; // syntax error:
   ^
   ;
p289.cpp:37:16: error: 'noreturn' attribute cannot be applied to types
operator int [[noreturn]] (); // error: noreturn attribute applied to a type
               ^
p289.cpp:37:1: error: conversion function must be a non-static member function
operator int [[noreturn]] (); // error: noreturn attribute applied to a type
^
6 errors generated.

$ g++-7 p289.cpp
p289.cpp: In function 'void h(Z)':
p289.cpp:23:8: error: conversion from 'Z' to non-scalar type 'Y' requested
 Y y2 = z; // ill-formed: copy-initialization
        ^
p289.cpp: At global scope:
p289.cpp:33:4: error: expected constructor, destructor, or type conversion before '.' token
 &ac.operator int*i; // syntax error:
    ^
p289.cpp:37:29: error: expected constructor, destructor, or type conversion before ';' token
 operator int [[noreturn]] (); // error: noreturn attribute applied to a type
                             ^