============
Data Caching
============

$Id$

  >>> from cybertools.util import cache
  >>> cache = cache.internalCache

  >>> @cache(lambda *args: 'calc')
  ... def calculate():
  ...     print 'calculating'
  ...     return 42

  >>> calculate()
  calculating
  42
  >>> calculate()
  42

  >>> class Demo(object):
  ...     id = '4711'
  ...     def getId(self, *args):
  ...         return self.id
  ...     @cache(getId)
  ...     def calculate(self):
  ...         print 'calculating'
  ...         return 42

  >>> demo = Demo()
  >>> demo.calculate()
  calculating
  42
  >>> demo.calculate()
  42

  >>> demo.id = '4712'
  >>> demo.calculate()
  calculating
  42
  >>> demo.calculate()
  42