Binder Classes

Collaboration diagram for Binder Classes:

Namespaces
	std::placeholders

Classes
struct	std::_Placeholder< _Num >
class	std::binder1st< _Operation >
class	std::binder2nd< _Operation >
struct	std::is_bind_expression< _Tp >
struct	std::is_bind_expression< _Bind< _Signature > >
struct	std::is_bind_expression< _Bind_result< _Result, _Signature > >
struct	std::is_bind_expression< const _Bind< _Signature > >
struct	std::is_bind_expression< const _Bind_result< _Result, _Signature > >
struct	std::is_bind_expression< const volatile _Bind< _Signature > >
struct	std::is_bind_expression< const volatile _Bind_result< _Result, _Signature > >
struct	std::is_bind_expression< volatile _Bind< _Signature > >
struct	std::is_bind_expression< volatile _Bind_result< _Result, _Signature > >
struct	std::is_placeholder< _Tp >
struct	std::is_placeholder< _Placeholder< _Num > >

Functions
template<typename _Func , typename... _BoundArgs>
_Bind_helper< __is_socketlike< _Func >::value, _Func, _BoundArgs... >::type	std::bind (_Func &&__f, _BoundArgs &&... __args)
template<typename _Result , typename _Func , typename... _BoundArgs>
_Bindres_helper< _Result, _Func, _BoundArgs... >::type	std::bind (_Func &&__f, _BoundArgs &&... __args)
template<typename _Operation , typename _Tp >
binder1st< _Operation >	std::bind1st (const _Operation &__fn, const _Tp &__x)
template<typename _Operation , typename _Tp >
binder2nd< _Operation >	std::bind2nd (const _Operation &__fn, const _Tp &__x)

Detailed Description

Binders turn functions/functors with two arguments into functors with a single argument, storing an argument to be applied later. For example, a variable B of type binder1st is constructed from a functor f and an argument x. Later, B's operator() is called with a single argument y. The return value is the value of f(x,y). B can be called with various arguments (y1, y2, ...) and will in turn call f(x,y1), f(x,y2), ...

The function bind1st is provided to save some typing. It takes the function and an argument as parameters, and returns an instance of binder1st.

The type binder2nd and its creator function bind2nd do the same thing, but the stored argument is passed as the second parameter instead of the first, e.g., bind2nd(std::minus<float>(),1.3) will create a functor whose operator() accepts a floating-point number, subtracts 1.3 from it, and returns the result. (If bind1st had been used, the functor would perform 1.3 - x instead.

Creator-wrapper functions like bind1st are intended to be used in calling algorithms. Their return values will be temporary objects. (The goal is to not require you to type names like std::binder1st<std::plus<int>> for declaring a variable to hold the return value from bind1st(std::plus<int>(),5).

These become more useful when combined with the composition functions.

These functions are deprecated in C++11 and can be replaced by std::bind (or std::tr1::bind) which is more powerful and flexible, supporting functions with any number of arguments. Uses of bind1st can be replaced by std::bind(f, x, std::placeholders::_1) and bind2nd by std::bind(f, std::placeholders::_1, x).

Function Documentation

bind() [1/2]

template<typename _Func , typename... _BoundArgs>

_Bind_helper<__is_socketlike<_Func>::value, _Func, _BoundArgs...>::type std::bind ( _Func &&  __f, _BoundArgs &&...  __args  )

inline

Function template for std::bind.

Definition at line 808 of file functional.

bind() [2/2]

template<typename _Result , typename _Func , typename... _BoundArgs>

_Bindres_helper<_Result, _Func, _BoundArgs...>::type std::bind ( _Func &&  __f, _BoundArgs &&...  __args  )

inline

Function template for std::bind<R>.

Definition at line 832 of file functional.

bind1st()

template<typename _Operation , typename _Tp >

binder1st<_Operation> std::bind1st ( const _Operation &  __fn, const _Tp &  __x  )

inline

One of the binder functors.

Definition at line 135 of file binders.h.

bind2nd()

template<typename _Operation , typename _Tp >

binder2nd<_Operation> std::bind2nd ( const _Operation &  __fn, const _Tp &  __x  )

inline

One of the binder functors.

Definition at line 170 of file binders.h.