Class memoize

source code

object --+
         |
        memoize

Decorator to use automatic memoization on a given function, such
that results are chached and, if called a second time, the
function will return the cached value. Example::

    @memoize
    def fibonacci(n):
        print "Computing fibonacci of:", n
        if n == 0:
            return 0
        if n == 1:
            return 1
        return fibonacci(n-1) + fibonacci(n-2)

    fibonacci(5)

If we removed the @memoize decorator, it would print O(2^n) lines
instead showing a exponential degeneration due to the binary
recursion.  However, already computed values will not recurse,
thus this program will print on the console:

    Computing fibonacci of: 5
    Computing fibonacci of: 4
    Computing fibonacci of: 3
    Computing fibonacci of: 2
    Computing fibonacci of: 1

Note that every computed value is cached in global state, so this
can be inapropiate when the function domain is very big.