bpo-17188: DOC: Document 'from None' in raise statement (#1671)
Original patch by Dennis Mårtensson.
diff --git a/Doc/reference/simple_stmts.rst b/Doc/reference/simple_stmts.rst
index 63d0ea5..2429f11 100644
--- a/Doc/reference/simple_stmts.rst
+++ b/Doc/reference/simple_stmts.rst
@@ -587,7 +587,7 @@
...
Traceback (most recent call last):
File "<stdin>", line 2, in <module>
- ZeroDivisionError: int division or modulo by zero
+ ZeroDivisionError: division by zero
The above exception was the direct cause of the following exception:
@@ -606,7 +606,7 @@
...
Traceback (most recent call last):
File "<stdin>", line 2, in <module>
- ZeroDivisionError: int division or modulo by zero
+ ZeroDivisionError: division by zero
During handling of the above exception, another exception occurred:
@@ -614,9 +614,27 @@
File "<stdin>", line 4, in <module>
RuntimeError: Something bad happened
+Exception chaining can be explicitly suppressed by specifying :const:`None` in
+the ``from`` clause::
+
+ >>> try:
+ ... print(1 / 0)
+ ... except:
+ ... raise RuntimeError("Something bad happened") from None
+ ...
+ Traceback (most recent call last):
+ File "<stdin>", line 4, in <module>
+ RuntimeError: Something bad happened
+
Additional information on exceptions can be found in section :ref:`exceptions`,
and information about handling exceptions is in section :ref:`try`.
+.. versionchanged:: 3.3
+ :const:`None` is now permitted as ``Y`` in ``raise X from Y``
+
+.. versionadded:: 3.3
+ The ``__suppress_context__`` attribute to suppress automatic display of the
+ exception context
.. _break:
diff --git a/Misc/ACKS b/Misc/ACKS
index 246a50b..d00fa79 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -965,6 +965,7 @@
Doug Marien
Sven Marnach
Alex Martelli
+Dennis Mårtensson
Anthony Martin
Owen Martin
Sidney San Martín