| .. Algorithms/Transformation Algorithms//reverse_replace_if |150 |
| |
| reverse_replace_if |
| ================== |
| |
| |
| Synopsis |
| -------- |
| |
| .. parsed-literal:: |
| |
| template< |
| typename Sequence |
| , typename Pred |
| , typename In = |unspecified| |
| > |
| struct reverse_replace_if |
| { |
| typedef |unspecified| type; |
| }; |
| |
| |
| |
| Description |
| ----------- |
| |
| Returns a reversed copy of the original sequence where every type that satisfies |
| the predicate ``Pred`` has been replaced with ``NewType``. |
| |
| |transformation algorithm disclaimer| |
| |
| Header |
| ------ |
| |
| .. parsed-literal:: |
| |
| #include <boost/mpl/replace_if.hpp> |
| |
| |
| |
| Model of |
| -------- |
| |
| |Reversible Algorithm| |
| |
| |
| Parameters |
| ---------- |
| |
| +---------------+-----------------------------------+-------------------------------+ |
| | Parameter | Requirement | Description | |
| +===============+===================================+===============================+ |
| | ``Sequence`` | |Forward Sequence| | An original sequence. | |
| +---------------+-----------------------------------+-------------------------------+ |
| | ``Pred`` | Unary |Lambda Expression| | A replacement condition. | |
| +---------------+-----------------------------------+-------------------------------+ |
| | ``NewType`` | Any type | A type to replace with. | |
| +---------------+-----------------------------------+-------------------------------+ |
| | ``In`` | |Inserter| | An inserter. | |
| +---------------+-----------------------------------+-------------------------------+ |
| |
| |
| Expression semantics |
| -------------------- |
| |
| |Semantics disclaimer...| |Reversible Algorithm|. |
| |
| For any |Forward Sequence| ``s``, an unary |Lambda Expression| ``pred``, |
| an |Inserter| ``in``, and arbitrary type ``x``: |
| |
| |
| .. parsed-literal:: |
| |
| typedef reverse_replace_if<s,pred,x,in>::type r; |
| |
| :Return type: |
| A type. |
| |
| :Semantics: |
| Equivalent to |
| |
| .. parsed-literal:: |
| |
| typedef lambda<pred>::type p; |
| typedef reverse_transform< s, if_< apply_wrap1<p,_1>,x,_1>, in >::type r; |
| |
| |
| Complexity |
| ---------- |
| |
| Linear. Performs exactly ``size<s>::value`` applications of ``pred``, and at most |
| ``size<s>::value`` insertions. |
| |
| |
| Example |
| ------- |
| |
| .. parsed-literal:: |
| |
| typedef vector_c<int,1,4,5,2,7,5,3,5> numbers; |
| typedef vector_c<int,1,4,0,2,0,0,3,0> expected; |
| typedef reverse_replace_if< |
| numbers |
| , greater< _, int_<4> > |
| , int_<0> |
| , front_inserter< vector<> > |
| >::type result; |
| |
| BOOST_MPL_ASSERT(( equal< result,expected, equal_to<_,_> > )); |
| |
| |
| See also |
| -------- |
| |
| |Transformation Algorithms|, |Reversible Algorithm|, |replace_if|, |reverse_replace|, |remove_if|, |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) |
