patterns Directory Reference

## Files

file | composite.hpp
| composite pattern
file | curiouslyrecurring.hpp
| Curiously recurring template pattern.
file | lazyobject.hpp
| framework for calculation on demand and result caching
file | observable.hpp
| observer/observable pattern
file | singleton.hpp
| basic support for the singleton pattern
file | visitor.hpp
| degenerate base class for the Acyclic Visitor pattern