.. Algorithms/Transformation Algorithms//replace |40

replace

Synopsis

.. parsed-literal::

template<
      typename Sequence
    , typename OldType
    , typename NewType
    , typename In = |unspecified|
    >
struct replace
{
    typedef |unspecified| type;
};

Description

Returns a copy of the original sequence where every type identical to OldType has been replaced with NewType.

|transformation algorithm disclaimer|

Header

.. parsed-literal::

#include <boost/mpl/replace.hpp>

Model of

|Reversible Algorithm|

Parameters

+---------------+-----------------------------------+-------------------------------+ | Parameter | Requirement | Description | +===============+===================================+===============================+ | Sequence | |Forward Sequence| | A original sequence. | +---------------+-----------------------------------+-------------------------------+ | OldType | Any type | A type to be replaced. | +---------------+-----------------------------------+-------------------------------+ | NewType | Any type | A type to replace with. | +---------------+-----------------------------------+-------------------------------+ | In | |Inserter| | An inserter. | +---------------+-----------------------------------+-------------------------------+

Expression semantics

|Semantics disclaimer...| |Reversible Algorithm|.

For any |Forward Sequence| s, an |Inserter| in, and arbitrary types x and y:

.. parsed-literal::

typedef replace<s,x,y,in>::type r; 

:Return type: A type.

:Semantics: Equivalent to

.. parsed-literal::

    typedef replace_if< s,y,is_same<_,x>,in >::type r; 

Complexity

Linear. Performs exactly size<s>::value comparisons for identity / insertions.

Example

.. parsed-literal::

typedef vector<int,float,char,float,float,double> types;
typedef vector<int,double,char,double,double,double> expected;
typedef replace< types,float,double >::type result;

BOOST_MPL_ASSERT(( equal< result,expected > ));

See also

|Transformation Algorithms|, |Reversible Algorithm|, |reverse_replace|, |replace_if|, |remove|, |transform|

.. copyright:: Copyright 2001-2009 Aleksey Gurtovoy and David Abrahams Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)