yield — Expert Playground

Pauses a generator function and produces a value to the caller

Python Playground

def running_average():
    total = 0
    count = 0
    average = None
    while True:
        value = yield average
        if value is None:
            break
        total += value
        count += 1
        average = total / count

# Drive the coroutine
gen = running_average()
next(gen)  # Prime the generator

for v in [10, 20, 30, 40, 50]:
    avg = gen.send(v)
    print(f"Added {v}, running average: {avg}")

# Generator state inspection
import inspect
def simple():
    yield 1
    yield 2

g = simple()
print(f"\nState: {inspect.getgeneratorstate(g)}")
next(g)
print(f"State: {inspect.getgeneratorstate(g)}")
list(g)
print(f"State: {inspect.getgeneratorstate(g)}")

Output

Click "Run" to execute your code

gen.send(value) resumes the generator and passes a value in through the yield expression. This enables coroutine-style bidirectional communication.

Challenge

Try modifying the code above to explore different behaviors. Can you extend the example to handle a new use case?

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