* URLs
* namespace support (auto-using with ambiguity resolution).
* more informative parser error handling (more context)
* aliases
* interface for not copying subobjects in printing functions
* lexer macros
* variable references
* ParamSet variables not referencing real variables
* other error reporting schemes (prints)
* ambiguity resolution with NULL matching a pointer type only (do we want this ?)
* parser support (and canonical name mapping) for template parameters that aren't types
  i.e. matrix<3,4>
* unloading of dynamically loaded libraries (when?)
* Option for echoing the value of values input (especially from command line).