| .. Algorithms/Querying Algorithms//equal |100 |
| |
| equal |
| ===== |
| |
| Synopsis |
| -------- |
| |
| .. parsed-literal:: |
| |
| template< |
| typename Seq1 |
| , typename Seq2 |
| , typename Pred = is_same<_1,_2> |
| > |
| struct equal |
| { |
| typedef |unspecified| type; |
| }; |
| |
| |
| |
| Description |
| ----------- |
| |
| Returns a true-valued |Integral Constant| if the two sequences ``Seq1`` |
| and ``Seq2`` are identical when compared element-by-element. |
| |
| |
| Header |
| ------ |
| |
| .. parsed-literal:: |
| |
| #include <boost/mpl/equal.hpp> |
| |
| |
| |
| Parameters |
| ---------- |
| |
| +-------------------+-------------------------------+-----------------------------------+ |
| | Parameter | Requirement | Description | |
| +===================+===============================+===================================+ |
| | ``Seq1``, ``Seq2``| |Forward Sequence| | Sequences to compare. | |
| +-------------------+-------------------------------+-----------------------------------+ |
| | ``Pred`` | Binary |Lambda Expression| | A comparison criterion. | |
| +-------------------+-------------------------------+-----------------------------------+ |
| |
| |
| Expression semantics |
| -------------------- |
| |
| For any |Forward Sequence|\ s ``s1`` and ``s2`` and a binary |Lambda Expression| ``pred``: |
| |
| |
| .. parsed-literal:: |
| |
| typedef equal<s1,s2,pred>::type c; |
| |
| :Return type: |
| |Integral Constant| |
| |
| :Semantics: |
| ``c::value == true`` is and only if ``size<s1>::value == size<s2>::value`` |
| and for every iterator ``i`` in |begin/end<s1>| ``deref<i>::type`` is identical to |
| |
| .. parsed-literal:: |
| |
| advance< begin<s2>::type, distance< begin<s1>::type,i >::type >::type |
| |
| |
| Complexity |
| ---------- |
| |
| Linear. At most ``size<s1>::value`` comparisons. |
| |
| |
| Example |
| ------- |
| |
| .. parsed-literal:: |
| |
| typedef vector<char,int,unsigned,long,unsigned long> s1; |
| typedef list<char,int,unsigned,long,unsigned long> s2; |
| |
| BOOST_MPL_ASSERT(( equal<s1,s2> )); |
| |
| |
| See also |
| -------- |
| |
| |Querying Algorithms|, |find|, |find_if| |
| |
| |
| .. 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) |
