compose()

sigc::compose() combines two or three arbitrary functors. More...

Classes
struct	sigc::compose1_functor< T_setter, T_getter >
	Adaptor that combines two functors. More...
struct	sigc::compose2_functor< T_setter, T_getter1, T_getter2 >
	Adaptor that combines three functors. More...

Functions
template<class T_setter , class T_getter >
compose1_functor< T_setter, T_getter >	sigc::compose (const T_setter & _A_setter, const T_getter & _A_getter)
	Creates an adaptor of type sigc::compose1_functor which combines two functors. More...
template<class T_setter , class T_getter1 , class T_getter2 >
compose2_functor< T_setter, T_getter1, T_getter2 >	sigc::compose (const T_setter & _A_setter, const T_getter1 & _A_getter1, const T_getter2 & _A_getter2)
	Creates an adaptor of type sigc::compose2_functor which combines three functors. More...

Detailed Description

sigc::compose() combines two or three arbitrary functors.

On invokation, parameters are passed on to one or two getter functor(s). The return value(s) are then passed on to the setter function.

Examples:

float square_root(float a)  { return sqrtf(a); }
float sum(float a, float b) { return a+b; }
std::cout << sigc::compose(&square_root, &sum)(9, 16); // calls square_root(sum(3,6))
std::cout << sigc::compose(&sum, &square_root, &square_root)(9); // calls sum(square_root(9), square_root(9))

The functor sigc::compose() returns can be passed directly into sigc::signal::connect().

Example:

sigc::signal<float,float,float> some_signal;
some_signal.connect(sigc::compose(&square_root, &sum));

Function Documentation

compose() [1/2]

template <class T_setter , class T_getter >

compose1_functor< T_setter, T_getter > sigc::compose ( const T_setter &  _A_setter, const T_getter &  _A_getter  )

inline

Creates an adaptor of type sigc::compose1_functor which combines two functors.

Parameters

_A_setter	Functor that receives the return value of the invokation of _A_getter.
_A_getter	Functor to invoke from operator()().

Returns

Adaptor that executes _A_setter with the value returned from invokation of _A_getter.

compose() [2/2]

template <class T_setter , class T_getter1 , class T_getter2 >

compose2_functor< T_setter, T_getter1, T_getter2 > sigc::compose ( const T_setter &  _A_setter, const T_getter1 &  _A_getter1, const T_getter2 &  _A_getter2  )

inline

Creates an adaptor of type sigc::compose2_functor which combines three functors.

Parameters

_A_setter	Functor that receives the return values of the invokation of _A_getter1 and _A_getter2.
_A_getter1	Functor to invoke from operator()().
_A_getter2	Functor to invoke from operator()().

Returns

Adaptor that executes _A_setter with the values return from invokation of _A_getter1 and _A_getter2.