在用户代码中提出的异常中，发电机中的子句除了子句以外的触发器

Question

我有一系列嵌套的发电机，我想从第一个生成器中知道，如果用户代码中的异常为示例，请考虑以下代码：

#############################################################################
def generator():
    try:
        for i in (1, 2, 3, 4, 5, 6):
            print(f"Generator: {i}.")
            yield i
    except:
        print("Exception handled in generator")
        raise

#############################################################################
def intermediary_generator():
    try:
        gen = generator()
        while i := gen.send(None):
            print(f"Intermediary generator: {i}.")
            yield i
    except StopIteration:
        pass
    except:
        print ("Exception handled in intermediary generator")
        raise

############################################################################
user_code_generator = intermediary_generator()
try:
    while i := user_code_generator.send(None):
        print(f"User code generator: {i}.")
        if i == 4:
            raise Exception("The exception in the user code")
except StopIteration:
    pass
except:
    print("Exception handled in user code generator")
    raise

我需要用户代码中的例外来传播对于中介机构和主发电机，我期望按照打印语句进行以下序列：

Exception handled in generator
Exception handled in intermediary generator
Exception handled in user code generator

但是，如果我执行上面的代码，则不会看到在发电机或中间发电机中处理的异常。

Answer 1

我想我会回答自己的问题，生成器的投掷方法正是我需要的，这将用户代码中的异常传播到主发电机。

#############################################################################
def generator():
    try:
        for i in (1, 2, 3, 4, 5, 6):
            print(f"Generator: {i}.")
            yield i
    except:
        print("Exception handled in generator")
        raise

#############################################################################
def intermediary_generator():
    try:
        gen = generator()
        while i := gen.send(None):
            print(f"Intermediary generator: {i}.")
            yield i
    except StopIteration:
        print("Stop iteration in intermediary generator")
    except Exception as exc:
        print ("Exception handled in intermediary generator")
        gen.throw(exc)
        raise

############################################################################
user_code_generator = intermediary_generator()
try:
    while i := user_code_generator.send(None):
        print(f"User code generator: {i}.")
        if i == 4:
            raise Exception("The exception in the user code")
except StopIteration:
    pass
except Exception as exc:
    print("Exception handled in user code generator")
    user_code_generator.throw(exc)
    raise

和输出：

Generator: 1.
Intermediary generator: 1.
User code generator: 1.
Generator: 2.
Intermediary generator: 2.
User code generator: 2.
Generator: 3.
Intermediary generator: 3.
User code generator: 3.
Generator: 4.
Intermediary generator: 4.
User code generator: 4.
Exception handled in user code generator
Exception handled in intermediary generator
Exception handled in generator
Traceback (most recent call last):
  File "<string>", line 39, in <module>
  File "<string>", line 25, in intermediary_generator
  File "<string>", line 9, in generator
  File "<string>", line 20, in intermediary_generator
  File "<string>", line 34, in <module>
Exception: The exception in the user code