yield from

[DeaD_EyE]

# removed the * in front of iterables
print("Definition of generator-function")


def join(iterables, joiner):
    print("First step of generator")
    # spliting iterable in first iterable and the rest
    first, *rest = iterables

    # yield each element from first
    yield from first
    # here the generator pauses until
    # next iteration

    print("Second step of generator")
    for iterable in rest:
        # yield joiner
        print("yield")
        yield joiner

        # yield each element from iterable from rest
        print("yield from")
        yield from iterable


# example
my_iterables = (
    range(3),
    range(4),
    range(2),
)
print("Calling generator-function")
gen = join(my_iterables, "-")
# generator
print("Generator:", gen)
print("Code inside the generator is not executed yet")
print("Iterating over generator with list(gen)")
print()
result = list(gen)  # <- this consumes the generator

# Now the generator is empy
print("Trying to consume gen again: ", list(gen))
print("But the generator is exhausted.")
print("Example with a for-loop")
print()
for element in join(my_iterables, "-"):
    print(element, type(element))