Summary - Generators

Combine yield, yield from and send to write a log stream.

Summary - Generators

In this group we covered defining generators with yield, the generator object and the next() call, publishing inner generators with yield from, sending values and errors with send and throw, and terminating with close.

Generators work lazily and do not hold all data in memory. yield produces and pauses; next advances; yield from wires an inner generator; send sends a value; close terminates. Now we'll write an example that combines these.

Exercise Combined summary example

Define the function def gen():. In the body include yield 1, yield from [2, 3] and yield 4. Then print all values with print(list(gen())).

Show example solution

# Write a generator with yield and yield from
def gen():
    yield 1
    yield from [2, 3]
    yield 4

print(list(gen()))

Test yourself

Which construct publishes an inner generator?
- yield
- yield from
- send
- close
Show answer

yield from — yield from publishes all values from an inner generator.
Match the generator concepts

yield

Produce value
next

Advance
yield from

Inner generator
close

Terminate

yield from line

def gen():
    yield 1
    ____ [2, 3]
    yield 4

Show answer

def gen():
    yield 1
    yield from [2, 3]
    yield 4

Match the summary example parts

def gen

Generator definition
yield 1

Single value
yield from [2, 3]

List publish
print(list(gen()))

List result

Next lesson: with statement

We Are Enhancing Your Experience

Cookie Preferences

Strictly Necessary Cookies

Analytical Cookies