What are some common iterator patterns in Python?

What are some common iterator patterns in Python?

In Python, common iterator patterns include generator functions, list comprehensions, and the use of the iter() and next() functions.

Can you explain how generator functions work?

Sure! Generator functions use the yield keyword to produce a series of values lazily, allowing you to iterate over them without storing them all in memory.

What is the difference between a generator and a list comprehension?

A generator produces items one at a time and only when requested, while a list comprehension creates a complete list in memory.

Can you give an example of a generator function?

Absolutely! Here's a simple example:

def count_up_to(n):
    count = 1
    while count <= n:
        yield count
        count += 1

This function generates numbers from 1 to n.

How can I use the iter() function with a custom class?

You can define the __iter__() and __next__() methods in your class to make it iterable. Here's a quick example:

class MyIterator:
    def __init__(self, limit):
        self.limit = limit
        self.current = 0

    def __iter__(self):
        return self

    def __next__(self):
        if self.current < self.limit:
            self.current += 1
            return self.current
        else:
            raise StopIteration