pointer_to_binary_function Class
The latest version of this topic can be found at pointer_to_binary_function Class.
Converts a binary function pointer into an adaptable binary function.
Syntax
template <class Arg1, class Arg2, class Result>
class pointer_to_binary_function
: public binary_function <Arg1, Arg2, Result>
{
public:
explicit pointer_to_binary_function(
Result (* _pfunc)(Arg1, Arg2));
Result operator()(
Arg1 left,
Arg2 right) const;
};
Parameters
_pfunc
The binary function to be converted.
left
The left object that the *_pfunc is called on.
right
The right object that the *_pfunc is called on.
Return Value
The template class stores a copy of _pfunc. It defines its member function operator()
as returning (* _pfunc)(_ Left, _ Right).
Remarks
A binary function pointer is a function object and may be passed to any Standard Template Library algorithm that is expecting a binary function as a parameter, but it is not adaptable. To use it with an adaptor, such as binding a value to it or using it with a negator, it must be supplied with the nested types first_argument_type, second_argument_type, and result_type that make such an adaptation possible. The conversion by pointer_to_binary_function
allows the function adaptors to work with binary function pointers.
Example
The constructor of pointer_to_binary_function
is rarely used directly. See the helper function ptr_fun for an example of how to declare and use the pointer_to_binary_function
adaptor predicate.
Requirements
Header: <functional>
Namespace: std