libzypp  17.28.8
Function.h
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12 #ifndef ZYPP_BASE_FUNCTION_H
13 #define ZYPP_BASE_FUNCTION_H
14 
15 #include <boost/function.hpp>
16 #define BOOST_BIND_GLOBAL_PLACEHOLDERS
17 #include <boost/bind.hpp>
18 #include <boost/ref.hpp>
19 
21 namespace zypp
22 {
23 
24  /* http://www.boost.org/doc/html/function.html
25 
26  The Boost.Function library contains a family of class templates
27  that are function object wrappers. The notion is similar to a
28  generalized callback. It shares features with function pointers
29  in that both define a call interface (e.g., a function taking
30  two integer arguments and returning a floating-point value)
31  through which some implementation can be called, and the
32  implementation that is invoked may change throughout the
33  course of the program.
34 
35  Generally, any place in which a function pointer would be used
36  to defer a call or make a callback, Boost.Function can be used
37  instead to allow the user greater flexibility in the implementation
38  of the target. Targets can be any 'compatible' function object
39  (or function pointer), meaning that the arguments to the interface
40  designated by Boost.Function can be converted to the arguments of
41  the target function object.
42  */
43  using boost::function;
44 
45  /* http://www.boost.org/libs/bind/bind.html
46 
47  boost::bind is a generalization of the standard functions std::bind1st
48  and std::bind2nd. It supports arbitrary function objects, functions,
49  function pointers, and member function pointers, and is able to bind
50  any argument to a specific value or route input arguments into arbitrary
51  positions. bind does not place any requirements on the function object;
52  in particular, it does not need the result_type, first_argument_type and
53  second_argument_type standard typedefs.
54  */
55  using boost::bind;
56 
57  /* http://www.boost.org/doc/html/ref.html
58 
59  The Ref library is a small library that is useful for passing references
60  to function templates (algorithms) that would usually take copies of their
61  arguments. It defines the class template boost::reference_wrapper<T>, the
62  two functions boost::ref and boost::cref that return instances of
63  boost::reference_wrapper<T>, and the two traits classes
64  boost::is_reference_wrapper<T> and boost::unwrap_reference<T>.
65 
66  The purpose of boost::reference_wrapper<T> is to contain a reference to an
67  object of type T. It is primarily used to "feed" references to function
68  templates (algorithms) that take their parameter by value.
69 
70  To support this usage, boost::reference_wrapper<T> provides an implicit
71  conversion to T&. This usually allows the function templates to work on
72  references unmodified.
73  */
74  using boost::ref;
75 
77 } // namespace zypp
79 #endif // ZYPP_BASE_FUNCTION_H
Easy-to use interface to the ZYPP dependency resolver.
Definition: CodePitfalls.doc:2