Question

I have a class something like :

def compute():
    # CPU savy task
    return some_value

def compute_other():
    # CPU savy task
    return some_value

class myclass:

    @property
    def value:
        # return if already computed => What can be done ?
        computed_value = compute()
        return computed_value

    @property
    def other:
        # return if already computed => What can be done ?
        computed_value = compute_other()
        return computed_value

ob = myclass()
print ob.value, ob.other
print ob.value, ob.other
print ob.value, ob.other

How can I intercept the method call to value and other and return the values if already available.

Can __getattribute__(self,name) be used to intercept any property and lookup if already available in self.__dict__ ?

Answer 1

Implement a memoization decorator and just apply it to your class:

@memoize
@property
    def value:
        # return if already computed => What can be done ?
        computed_value = compute()
        return computed_value

http://wiki.python.org/moin/PythonDecoratorLibrary#Memoize