I use custom stl allocator to replace std::basic_string like this:
 
    typedef std::basic_string<char, std::char_traits<char>, MySTLAllocator<char> > MyString;
 
    I want basic_ptree can use my allocator to do parse work, so I write code like this:
    typedef boost::property_tree::basic_ptree<MyString, MyString> PropertyTree;
    PropertyTree propertyTree;
    boost::property_tree::read_ini(std::ifstream(configFile.c_str()), propertyTree);
 
    And I met error at ini_parser.hpp, line 109~111:
    Str key = property_tree::detail::trim(
    line.substr(1, end - 1), stream.getloc());
    if (local.find(key) != local.not_found())
 
    the Str is a typedef at the begin of this function:
    typedef std::basic_string<Ch> Str;
 
    So my custom string can not assign to the key, so it seems can not use custom allocator at all. There have the same problem in xml_parser.