https://github.com/python/cpython/commit/98d57737de73342d33d1b90dc0285f58646... commit: 98d57737de73342d33d1b90dc0285f586465d22b branch: 3.9 author: Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com> committer: miss-islington <31488909+miss-islington@users.noreply.github.com> date: 2022-03-31T07:24:39-07:00 summary: bpo-14911: Corrected generator.throw() documentation (GH-32207) Co-authored-by: Andrew Svetlov <andrew.svetlov@gmail.com> (cherry picked from commit 8be7c2bc5ad5e295f0f855bb31db412eef2c7c92) Co-authored-by: Dave Goncalves <davegoncalves@gmail.com> files: M Doc/howto/functional.rst M Doc/reference/datamodel.rst M Doc/reference/expressions.rst M Objects/genobject.c diff --git a/Doc/howto/functional.rst b/Doc/howto/functional.rst index c7f8bc8f17f43..695b9b31a762b 100644 --- a/Doc/howto/functional.rst +++ b/Doc/howto/functional.rst @@ -589,7 +589,7 @@ generator function. In addition to :meth:`~generator.send`, there are two other methods on generators: -* :meth:`throw(type, value=None, traceback=None) <generator.throw>` is used to +* :meth:`throw(value) <generator.throw>` is used to raise an exception inside the generator; the exception is raised by the ``yield`` expression where the generator's execution is paused. diff --git a/Doc/reference/datamodel.rst b/Doc/reference/datamodel.rst index 84320f41f6cae..033d65fd7c90f 100644 --- a/Doc/reference/datamodel.rst +++ b/Doc/reference/datamodel.rst @@ -2854,7 +2854,8 @@ generators, coroutines do not directly support iteration. :exc:`StopIteration`, or other exception) is the same as when iterating over the :meth:`__await__` return value, described above. -.. method:: coroutine.throw(type[, value[, traceback]]) +.. method:: coroutine.throw(value) + coroutine.throw(type[, value[, traceback]]) Raises the specified exception in the coroutine. This method delegates to the :meth:`~generator.throw` method of the iterator that caused diff --git a/Doc/reference/expressions.rst b/Doc/reference/expressions.rst index 4ffb6512107f2..502c022501eff 100644 --- a/Doc/reference/expressions.rst +++ b/Doc/reference/expressions.rst @@ -557,14 +557,27 @@ is already executing raises a :exc:`ValueError` exception. could receive the value. -.. method:: generator.throw(type[, value[, traceback]]) +.. method:: generator.throw(value) + generator.throw(type[, value[, traceback]]) - Raises an exception of type ``type`` at the point where the generator was paused, + Raises an exception at the point where the generator was paused, and returns the next value yielded by the generator function. If the generator exits without yielding another value, a :exc:`StopIteration` exception is raised. If the generator function does not catch the passed-in exception, or raises a different exception, then that exception propagates to the caller. + In typical use, this is called with a single exception instance similar to the + way the :keyword:`raise` keyword is used. + + For backwards compatability, however, the second signature is + supported, following a convention from older versions of Python. + The *type* argument should be an exception class, and *value* + should be an exception instance. If the *value* is not provided, the + *type* constructor is called to get an instance. If *traceback* + is provided, it is set on the exception, otherwise any existing + :attr:`~BaseException.__traceback__` attribute stored in *value* may + be cleared. + .. index:: exception: GeneratorExit diff --git a/Objects/genobject.c b/Objects/genobject.c index 5ba4de82ea70e..95614729c8fab 100644 --- a/Objects/genobject.c +++ b/Objects/genobject.c @@ -384,8 +384,11 @@ gen_close(PyGenObject *gen, PyObject *args) PyDoc_STRVAR(throw_doc, -"throw(typ[,val[,tb]]) -> raise exception in generator,\n\ -return next yielded value or raise StopIteration."); +"throw(value)\n\ +throw(type[,value[,tb]])\n\ +\n\ +Raise exception in generator, return next yielded value or raise\n\ +StopIteration."); static PyObject * _gen_throw(PyGenObject *gen, int close_on_genexit, @@ -943,8 +946,11 @@ PyDoc_STRVAR(coro_send_doc, return next iterated value or raise StopIteration."); PyDoc_STRVAR(coro_throw_doc, -"throw(typ[,val[,tb]]) -> raise exception in coroutine,\n\ -return next iterated value or raise StopIteration."); +"throw(value)\n\ +throw(type[,value[,traceback]])\n\ +\n\ +Raise exception in coroutine, return next iterated value or raise\n\ +StopIteration."); PyDoc_STRVAR(coro_close_doc, "close() -> raise GeneratorExit inside coroutine.");