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1.. Algorithms/Transformation Algorithms//replace |40
2
3replace
4=======
5
6Synopsis
7--------
8
9.. parsed-literal::
10
11    template<
12          typename Sequence
13        , typename OldType
14        , typename NewType
15        , typename In = |unspecified|
16        >
17    struct replace
18    {
19        typedef |unspecified| type;
20    };
21
22
23
24Description
25-----------
26
27Returns a copy of the original sequence where every type identical to ``OldType``
28has been replaced with ``NewType``.
29
30|transformation algorithm disclaimer|
31
32Header
33------
34
35.. parsed-literal::
36
37    #include <boost/mpl/replace.hpp>
38
39
40Model of
41--------
42
43|Reversible Algorithm|
44
45
46Parameters
47----------
48
49+---------------+-----------------------------------+-------------------------------+
50| Parameter     | Requirement                       | Description                   |
51+===============+===================================+===============================+
52| ``Sequence``  | |Forward Sequence|                | A original sequence.          |
53+---------------+-----------------------------------+-------------------------------+
54| ``OldType``   | Any type                          | A type to be replaced.        |
55+---------------+-----------------------------------+-------------------------------+
56| ``NewType``   | Any type                          | A type to replace with.       |
57+---------------+-----------------------------------+-------------------------------+
58| ``In``        | |Inserter|                        | An inserter.                  |
59+---------------+-----------------------------------+-------------------------------+
60
61
62Expression semantics
63--------------------
64
65|Semantics disclaimer...| |Reversible Algorithm|.
66
67For any |Forward Sequence| ``s``, an |Inserter| ``in``, and arbitrary types ``x`` and ``y``:
68
69
70.. parsed-literal::
71
72    typedef replace<s,x,y,in>::type r;
73
74:Return type:
75    A type.
76
77:Semantics:
78    Equivalent to
79
80    .. parsed-literal::
81
82        typedef replace_if< s,y,is_same<_,x>,in >::type r;
83
84
85Complexity
86----------
87
88Linear. Performs exactly ``size<s>::value`` comparisons for
89identity / insertions.
90
91
92Example
93-------
94
95.. parsed-literal::
96
97    typedef vector<int,float,char,float,float,double> types;
98    typedef vector<int,double,char,double,double,double> expected;
99    typedef replace< types,float,double >::type result;
100
101    BOOST_MPL_ASSERT(( equal< result,expected > ));
102
103
104See also
105--------
106
107|Transformation Algorithms|, |Reversible Algorithm|, |reverse_replace|, |replace_if|, |remove|, |transform|
108
109
110.. copyright:: Copyright �  2001-2009 Aleksey Gurtovoy and David Abrahams
111   Distributed under the Boost Software License, Version 1.0. (See accompanying
112   file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
113