[dcl.fct.def.general] (original) (raw)

9 Declarations [dcl]

9.6 Function definitions [dcl.fct.def]

9.6.1 General [dcl.fct.def.general]

Function definitions have the form

Any informal reference to the body of a function should be interpreted as a reference to the non-terminal function-body, including, for a constructor, default member initializers or default initialization used to initialize a base or member subobject in the absence of a mem-initializer-id ([class.base.init]).

A function shall be defined only in namespace or class scope.

The type of a parameter or the return type for a function definition shall not be a (possibly cv-qualified) class type that is incomplete or abstract within the function body unless the function is deleted ([dcl.fct.def.delete]).

[Example 1:

A simple example of a complete function definition isint max(int a, int b, int c) { int m = (a > b) ? a : b;return (m > c) ? m : c;}

[Note 2:

Unused parameters need not be named.

For example,

void print(int a, int) { std::printf("a = %d\n",a);} — _end note_]

A function-local predefined variable is a variable with static storage duration that is implicitly defined in a function parameter scope.

The function-local predefined variable __func__ is defined as if a definition of the formstatic const char __func__[] = "function-name";had been provided, where function-name is an implementation-defined string.

It is unspecified whether such a variable has an address distinct from that of any other object in the program.81

[Example 2: struct S { S() : s(__func__) { } // OK const char* s;};void f(const char* s = __func__); // error: __func__ is undeclared — _end example_]

81)81)

Implementations are permitted to provide additional predefined variables with names that are reserved to the implementation ([lex.name]).

If a predefined variable is not odr-used ([basic.def.odr]), its string value need not be present in the program image.