Subject: [Boost-commit] svn:boost r75477 - sandbox/variadic_templates/sandbox/stepper/boost/array_stepper
From: cppljevans_at_[hidden]
Date: 2011-11-13 09:34:04
Author: cppljevans
Date: 2011-11-13 09:34:03 EST (Sun, 13 Nov 2011)
New Revision: 75477
URL: http://svn.boost.org/trac/boost/changeset/75477
Log:
add missing file
Added:
sandbox/variadic_templates/sandbox/stepper/boost/array_stepper/permutation.hpp (contents, props changed)
Added: sandbox/variadic_templates/sandbox/stepper/boost/array_stepper/permutation.hpp
==============================================================================
--- (empty file)
+++ sandbox/variadic_templates/sandbox/stepper/boost/array_stepper/permutation.hpp 2011-11-13 09:34:03 EST (Sun, 13 Nov 2011)
@@ -0,0 +1,97 @@
+#ifndef BOOST_ARRAY_STEPPER_PERMUTAION_HPP_INCLUDED
+#define BOOST_ARRAY_STEPPER_PERMUTAION_HPP_INCLUDED
+#include <boost/array_stepper/mk_iota.hpp>
+#ifdef __GXX_EXPERIMENTAL_CXX0X__
+#include <algorithm>
+#endif
+#include <boost/assert.hpp>
+
+namespace boost
+{
+namespace array_stepper
+{
+struct permutation
+: private std::vector<unsigned>
+{
+ typedef std::vector<unsigned> permute_maybe_t;
+ typedef permute_maybe_t::value_type value_type;
+ typedef permute_maybe_t::const_iterator const_iterator;
+
+ permute_maybe_t const&impl()const
+ {
+ return *this;
+ }
+
+ unsigned operator[](unsigned i)const
+ {
+ return impl()[i];
+ }
+
+ typename permute_maybe_t::const_iterator begin()const
+ {
+ return impl().begin();
+ }
+
+ typename permute_maybe_t::const_iterator end()const
+ {
+ return impl().end();
+ }
+
+ static bool is_permutation(permute_maybe_t const& a_permute_maybe)
+ {
+ #ifdef __GXX_EXPERIMENTAL_CXX0X__
+ return
+ std::is_permutation
+ ( a_permute_maybe.begin()
+ , a_permute_maybe.end()
+ , mk_iota(value_type(0),value_type(a_permute_maybe.size())).begin()
+ );
+ #else
+ std::vector<bool> is_found(a_permute_maybe.size(),false);
+ unsigned num_found=0;
+ unsigned const n=a_permute_maybe.size();
+ for(unsigned i=0; i<n; ++i)
+ {
+ value_type j=a_permute_maybe[i];
+ if(n<=j) return false;
+ if(is_found[j]) return false;
+ is_found[j]=true;
+ ++num_found;
+ }
+ return num_found==n;
+ #endif
+ }
+
+ permutation(std::size_t s=0)
+ : permute_maybe_t(mk_iota(value_type(0),value_type(s)))
+ {}
+
+ permutation(permute_maybe_t const& a_permute_maybe_v)
+ : permute_maybe_t(a_permute_maybe_v)
+ {
+ BOOST_ASSERT(is_permutation(a_permute_maybe_v));
+ }
+
+ struct assert_is_permutation{};
+
+ permutation( assert_is_permutation, permute_maybe_t const& a_permute_maybe_v)
+ : permute_maybe_t(a_permute_maybe_v)
+ {}
+
+ permutation permute( permute_maybe_t const& other)
+ {
+ BOOST_ASSERT(is_permutation(other));
+ unsigned const n=other.size();
+ permute_maybe_t const&me=impl();
+ BOOST_ASSERT(n==me.size());
+ permute_maybe_t permuted(n);
+ for(unsigned i=0; i<n; ++i) permuted[i]=me[other[i]];
+ assert_is_permutation is_perm;
+ return permutation( is_perm, permuted);
+ }
+
+};
+
+}//exit array_stepper namespace
+}//exit boost namespace
+#endif