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+//////////////////////////////////////////////////////////////////////////////
+//
+// (C) Copyright Ion Gaztanaga 2015-2015. 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)
+//
+// See http://www.boost.org/libs/container for documentation.
+//
+//////////////////////////////////////////////////////////////////////////////
+//[doc_pmr_ShoppingList_hpp
+//ShoppingList.hpp
+#include <boost/container/pmr/vector.hpp>
+#include <boost/container/pmr/string.hpp>
+
+class ShoppingList
+{
+ // A vector of strings using polymorphic allocators. Every element
+ // of the vector will use the same allocator as the vector itself.
+ boost::container::pmr::vector_of
+ <boost::container::pmr::string>::type m_strvec;
+ //Alternatively in compilers that support template aliases:
+ // boost::container::pmr::vector<boost::container::pmr::string> m_strvec;
+ public:
+
+ // This makes uses_allocator<ShoppingList, memory_resource*>::value true
+ typedef boost::container::pmr::memory_resource* allocator_type;
+
+ // If the allocator is not specified, "m_strvec" uses pmr::get_default_resource().
+ explicit ShoppingList(allocator_type alloc = 0)
+ : m_strvec(alloc) {}
+
+ // Copy constructor. As allocator is not specified,
+ // "m_strvec" uses pmr::get_default_resource().
+ ShoppingList(const ShoppingList& other)
+ : m_strvec(other.m_strvec) {}
+
+ // Copy construct using the given memory_resource.
+ ShoppingList(const ShoppingList& other, allocator_type a)
+ : m_strvec(other.m_strvec, a) {}
+
+ allocator_type get_allocator() const
+ { return m_strvec.get_allocator().resource(); }
+
+ void add_item(const char *item)
+ { m_strvec.emplace_back(item); }
+
+ //...
+};
+
+//]]
+
+//[doc_pmr_main_cpp
+
+//=#include "ShoppingList.hpp"
+#include <cassert>
+#include <boost/container/pmr/list.hpp>
+#include <boost/container/pmr/monotonic_buffer_resource.hpp>
+
+void processShoppingList(const ShoppingList&)
+{ /**/ }
+
+int main()
+{
+ using namespace boost::container;
+ //All memory needed by folder and its contained objects will
+ //be allocated from the default memory resource (usually new/delete)
+ pmr::list_of<ShoppingList>::type folder; // Default allocator resource
+ //Alternatively in compilers that support template aliases:
+ // boost::container::pmr::list<ShoppingList> folder;
+ {
+ char buffer[1024];
+ pmr::monotonic_buffer_resource buf_rsrc(&buffer, 1024);
+
+ //All memory needed by temporaryShoppingList will be allocated
+ //from the local buffer (speeds up "processShoppingList")
+ ShoppingList temporaryShoppingList(&buf_rsrc);
+ assert(&buf_rsrc == temporaryShoppingList.get_allocator());
+
+ //list nodes, and strings "salt" and "pepper" will be allocated
+ //in the stack thanks to "monotonic_buffer_resource".
+ temporaryShoppingList.add_item("salt");
+ temporaryShoppingList.add_item("pepper");
+ //...
+
+ //All modifications and additions to "temporaryShoppingList"
+ //will use memory from "buffer" until it's exhausted.
+ processShoppingList(temporaryShoppingList);
+
+ //Processing done, now insert it in "folder",
+ //which uses the default memory resource
+ folder.push_back(temporaryShoppingList);
+ assert(pmr::get_default_resource() == folder.back().get_allocator());
+ //temporaryShoppingList, buf_rsrc, and buffer go out of scope
+ }
+ return 0;
+}
+
+//]