title: Data structure for storing strings?
body: <p>I'm looking for a data structure to store strings in. I require a function in the interface that takes a string as its only parameter and returns a reference/iterator/pointer/handle that can be used to retrieve the string for the rest of the lifetime of the data structure. Set membership, entry deletion etc. is not required.</p>
  
  <p>I'm more concerned with memory usage than speed.</p>