_codegen.hpp File Reference

Code generation macros and utilities. More...

Macros
#define	CXXO_DEFAULT_DEFAULT_CONSTRUCTOR(Type)   Type () = default [or equivalent]
	Declares a “ =default ” default constructor. More...
#define	CXXO_DEFAULT_COPY_CONSTRUCTOR(Type, Su, ...)
	Declares a =default copy constructor. More...
#define	CXXO_TYPEOF(expr)   __typeof__(expr) [or equivalent]
	Obtains the type of expr if there is a __typeof__-like facility to do so. More...

Detailed Description

Code generation macros and utilities.

Macro Definition Documentation

CXXO_DEFAULT_DEFAULT_CONSTRUCTOR

#define CXXO_DEFAULT_DEFAULT_CONSTRUCTOR

(

Type

)

Type () = default [or equivalent]

Declares a “ =default ” default constructor.

Codegen:

Using this macro in the body of a class will invoke, where available, the =default default constructor. In pre-C++11, it will invoke a throw() empty constructor.

class Foo {
        CXXO_DEFAULT_DEFAULT_CONSTRUCTOR(Foo);
        //In >= C++11 equivalent to:
        Foo () noexcept = default;

};

CXXO_DEFAULT_COPY_CONSTRUCTOR

#define CXXO_DEFAULT_COPY_CONSTRUCTOR	(		Type,
			Su,
			...
	)

Value:

[if >=C++11] Type (Type const& ) Su = default  \
    [else] Type (Type const& From) Su  : __VA_ARGS__ {}

Declares a =default copy constructor.

Parameters

Su	constructor suffix (eg.: noexcept)
...	Explicit constructor body (for C++03)

Codegen:

Using this macro in the body of a class invokes, starting with C++11, a =default copy constructor. In C++03, it generates the code for a copy constructor using the subsequent arguments to the macro as code for the member initializer list, using the variable name From for the argument of the copy constructor.

class Foo {
        CXXO_DEFAULT_COPY_CONSTRUCTOR(Foo,  , member(From.member) );
        //In >= C++11 equivalent to:
        Foo (Foo const&)  = default;
        //In < C++11 equivalent to:
        Foo (Foo const& From) : member(From.member) {}

        private:
        float member;

};

CXXO_TYPEOF

#define CXXO_TYPEOF

(

expr

)

__typeof__(expr) [or equivalent]

Obtains the type of expr if there is a __typeof__-like facility to do so.

Parameters

expr	An expression evaluating to a type. Since this is a macro, it can't take commas.

In C++11 onwards, this evaluates to decltype(expr) ; in other modes, it will ealuate to __typeof__(expr) if the feature is available or will error out if not.

Referenced by cxxomfort::cxxostd::bind_front(), and cxxomfort::cxxostd::invoke_r().