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+# shared_string
+
+Simple implementation of a shared string in C++ (C++11).
+
+All it does is wrap up a std::shared_ptr<const std::basic_string<CharT>> and give it std::basic_string interface, so it's feels like you're using a regular ol' std::string.  Almost all of the implemented methods are thin wrappers around the actual shared string.
+
+### Methods missing that exist in std::basic_string
+
+- reserve()
+- capacity()
+- shrink_to_fit()
+- append()
+- assign()
+- insert()
+- erase()
+- replace()
+- push_front()
+- push_back()
+- all methods that return a non-const iterator
+
+It's not meant for manipulating the string underneath.  If you need those methods, you should just use std::string.
+
+Note that you still get operator=() and clear().
+
+### Couldn’t I just use const std::string&?  
+
+Sure.  But it doesn’t help you if, for instance, you want to use those strings as keys in maps.  shared_string allows you to create lots of std::map<shared_string, MyType>’s and not incur a penalty for repeating the keys over and over again.
+
+### Couldn’t I use boost::const_string?
+
+You bet! And you should. But this has different semantics - if you initialize a shared_string with a const char *, a copy is made, and the shared_string takes ownership of that copy - just like std::string.  Just like std::string except that copying a shared_string doesn’t allocate new buffers.