Sandbox::https://github.com/KelvinMW/python-series/blob/master/src/additions/test

Repository navigation

"""Generators.

@see: https://www.learnpython.org/en/Generators

Generators are used to create iterators, but with a different approach. Generators are simple

functions which return an iterable set of items, one at a time, in a special way.

When an iteration over a set of item starts using the for statement, the generator is run. Once the

generator's function code reaches a "yield" statement, the generator yields its execution back to

the for loop, returning a new value from the set. The generator function can generate as many

values (possibly infinite) as it wants, yielding each one in its turn.

"""

import random

def lottery():

"""Generator function example.

Here is a simple example of a generator function which returns random integers.

This function decides how to generate the random numbers on its own, and executes the yield

statements one at a time, pausing in between to yield execution back to the main for loop.

"""

# returns first 3 random numbers between 1 and 10

# pylint: disable=unused-variable

for _ in range(3):

yield random.randint(1, 10)

# returns a 4th number between 10 and 20

yield random.randint(10, 20)

def test_generators():

"""Yield statement"""

for number_index, random_number in enumerate(lottery()):

if number_index < 3:

assert 0 <= random_number <= 10

else:

assert 10 <= random_number <= 20