mirrors/cpython
0
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2024-11-30 21:34:17 +08:00
Code Issues Packages Projects Releases Wiki Activity

Issue22988: clarify yield and exception blocks

Browse Source
This commit is contained in:
Ethan Furman 2015-01-14 22:26:04 -08:00
commit e62430eda4
1 changed files with 5 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
Doc/reference/expressions.rst
View File

@ -330,8 +330,9 @@ The execution starts when one of the generator's methods is called. At that
time, the execution proceeds to the first yield expression, where it is time, the execution proceeds to the first yield expression, where it is
suspended again, returning the value of :token:`expression_list` to the generator's suspended again, returning the value of :token:`expression_list` to the generator's
caller. By suspended, we mean that all local state is retained, including the caller. By suspended, we mean that all local state is retained, including the
current bindings of local variables, the instruction pointer, and the internal current bindings of local variables, the instruction pointer, the internal
evaluation stack. When the execution is resumed by calling one of the evaluation stack, and the state of any exception handling. When the execution
is resumed by calling one of the
generator's methods, the function can proceed exactly as if the yield expression generator's methods, the function can proceed exactly as if the yield expression
were just another external call. The value of the yield expression after were just another external call. The value of the yield expression after
resuming depends on the method which resumed the execution. If resuming depends on the method which resumed the execution. If
@ -348,8 +349,8 @@ suspended. The only difference is that a generator function cannot control
where the execution should continue after it yields; the control is always where the execution should continue after it yields; the control is always
transferred to the generator's caller. transferred to the generator's caller.
Yield expressions are allowed in the :keyword:`try` clause of a :keyword:`try` Yield expressions are allowed anywhere in a :keyword:`try` construct. If the
... :keyword:`finally` construct. If the generator is not resumed before it is generator is not resumed before it is
finalized (by reaching a zero reference count or by being garbage collected), finalized (by reaching a zero reference count or by being garbage collected),
the generator-iterator's :meth:`~generator.close` method will be called, the generator-iterator's :meth:`~generator.close` method will be called,
allowing any pending :keyword:`finally` clauses to execute. allowing any pending :keyword:`finally` clauses to execute.