micropython/tests/basics/generator-exc.py

# Test proper handling of exceptions within generator across yield
def gen():
    try:
        yield 1
        raise ValueError
    except ValueError:
        print("Caught")
    yield 2

for i in gen():
    print(i)


# Test throwing exceptions out of generator
def gen2():
    yield 1
    raise ValueError
    yield 2
    yield 3

g = gen2()
print(next(g))
try:
    print(next(g))
except ValueError:
    print("ValueError")

try:
    print(next(g))
except StopIteration:
    print("StopIteration")


# Test throwing exception into generator
def gen3():
    yield 1
    try:
        yield 2
    except ValueError:
        print("ValueError received")
        yield 3
    yield 4
    yield 5

g = gen3()
print(next(g))
print(next(g))
print("out of throw:", g.throw(ValueError))
print(next(g))
try:
    print("out of throw2:", g.throw(ValueError))
except ValueError:
    print("Boomerang ValueError caught")