diff options
Diffstat (limited to 'Include/frameobject.h')
| -rw-r--r-- | Include/frameobject.h | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/Include/frameobject.h b/Include/frameobject.h index d2afe8b..65ebd2a 100644 --- a/Include/frameobject.h +++ b/Include/frameobject.h @@ -27,13 +27,13 @@ typedef struct _frame { PyObject **f_stacktop; PyObject *f_trace; /* Trace function */ - /* If an exception is raised in this frame, the next three are used to - * record the exception info (if any) originally in the thread state. See - * comments before set_exc_info() -- it's not obvious. - * Invariant: if _type is NULL, then so are _value and _traceback. - * Desired invariant: all three are NULL, or all three are non-NULL. That - * one isn't currently true, but "should be". - */ + /* In a generator, we need to be able to swap between the exception + state inside the generator and the exception state of the calling + frame (which shouldn't be impacted when the generator "yields" + from an except handler). + These three fields exist exactly for that, and are unused for + non-generator frames. See the SAVE_EXC_STATE and SWAP_EXC_STATE + macros in ceval.c for details of their use. */ PyObject *f_exc_type, *f_exc_value, *f_exc_traceback; PyThreadState *f_tstate; |