id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
924	Convenience function for const map read	nobody		"It's really awkward to use an STL map when you have
only a const reference to it, because you cannot use
operator[] -- you have to use find, check if the value
was found, etc.  (The reason being that operator[]
creates a new map entry initialized with the null value
if it doesn't find the key.)  It would be much more
convenient to have
a lookup convenience function that either throws an
exception if the key doesn't exist, or returns a
default-initialized value.  The version that returns a
default value if the key doesn't exist might look
something like this:

{{{
template <class Map>
typename Map::data_type const &
map_get(Map const & m, typename Map::key_type key)
{
  static typename Map::data_type default_value;
  typename Map::const_iterator it = m.find(key);
  return (it == m.end() ? default_value : it->second);
}

}}}"	Feature Requests	closed	To Be Determined	None	Boost 1.34.0	Optimization	invalid