dlib C++ Library - std_allocator_ex.cpp

// The contents of this file are in the public domain. See LICENSE_FOR_EXAMPLE_PROGRAMS.txt
/*
 This is an example illustrating the use of the dlib::std_allocator object.
 In this example we will create the necessary typedefs to give the
 dlib::std_allocator object to the standard string and vector objects
 in the STL. Thus we will create versions of std::string and std::vector
 that perform all their memory allocations and deallocations via one of 
 the dlib memory manager objects.
*/
// include everything we need for this example
#include <vector>
#include <iostream>
#include <string>
#include <dlib/std_allocator.h>
#include <dlib/memory_manager.h>
#include <dlib/memory_manager_stateless.h>
using namespace std;
using namespace dlib;
int main()
{
 // Make a typedef for an allocator that uses the thread safe memory_manager_stateless object with a 
 // global memory pool. This version of the memory_manager_stateless object keeps everything it allocates
 // in a global memory pool and doesn't release any memory until the program terminates.
 typedef std_allocator<char, memory_manager_stateless<char>::kernel_2_3a> alloc_char_with_global_memory_pool;
 // Now make a typedef for a C++ standard string that uses our new allocator type
 typedef std::basic_string<char, char_traits<char>, alloc_char_with_global_memory_pool > dstring;
 // typedef another allocator for dstring objects
 typedef std_allocator<dstring, memory_manager_stateless<char>::kernel_2_3a> alloc_dstring_with_global_memory_pool;
 // Now make a typedef for a C++ standard vector that uses our new allocator type and also contains the new dstring
 typedef std::vector<dstring, alloc_dstring_with_global_memory_pool > dvector;
 // Now we can use the string and vector we have as we normally would. So for example, I can make a
 // dvector and add 4 strings into it like so:
 dvector v;
 v.push_back("one");
 v.push_back("two");
 v.push_back("three");
 v.push_back("four");
 // And now we print out the contents of our vector
 for (unsigned long i = 0; i < v.size(); ++i)
 {
 cout << v[i] << endl;
 }
}