Introduce a new builtin exception, UnboundLocalError, raised when ceval.c
tries to retrieve or delete a local name that isn't bound to a value.
Currently raises NameError, which makes this behavior a FAQ since the same
error is raised for "missing" global names too: when the user has a global
of the same name as the unbound local, NameError makes no sense to them.
Even in the absence of shadowing, knowing whether a bogus name is local or
global is a real aid to quick understanding.
Example:
D:\src\PCbuild>type local.py
x = 42
def f():
print x
x = 13
return x
f()
D:\src\PCbuild>python local.py
Traceback (innermost last):
File "local.py", line 8, in ?
f()
File "local.py", line 4, in f
print x
UnboundLocalError: x
D:\src\PCbuild>
Note that UnboundLocalError is a subclass of NameError, for compatibility
with existing class-exception code that may be trying to catch this as a
NameError. Unfortunately, I see no way to make this wholly compatible
with -X (see comments in bltinmodule.c): under -X, [UnboundLocalError
is an alias for NameError --GvR].
[The ceval.c patch differs slightly from the second version that Tim
submitted; I decided not to raise UnboundLocalError for DELETE_NAME,
only for DELETE_LOCAL. DELETE_NAME is only generated at the module
level, and since at that level a NameError is raised for referencing
an undefined name, it should also be raised for deleting one.]
Toby writes:
winmakemakefile.py tries to allow for spaces in the python install
path, by adding quotes around the appropriate filenames. It doesn't
quite get this correct; sometimes the quotes end up in the middle of
the path.
Microsoft's NMAKE version 6.0 is happy with this (!!!!) unless there
is also a space in the name. I guess most users of freeze on windows
do not use the same path as the binary distribution.
I've tested the following changes on systems with and without a space
in the path.
lots of markup fixes and some English nits fixed.
Still needs real review. Some of the function signatures used in this
module are really bad! (Two leading optional parameters? Ugh!)
We occasionally received reports from people getting "invalid tstate"
crashes (this is a fatal error in PyThreadState_Delete()). Finally
several people were able to reproduce it reliably and Tim Peters
discovered that there is a race condition when multiple threads are
calling this function without holding the global interpreter lock (the
function may be called without holding that).
Solved the race condition by adding a lock around the mutating uses of
interp->tstate_head. Tim and Jonathan Giddy have run tests that make
it likely that this fixes the crashes -- although Tim hasn't heard
from the person who reported the original problem.
always lowercasing the option name, call a method optionxform() which
can be overridden. Also make the regexps SECTRE and OPTRE non-private
variables so they can also be overridden.
mode attribute of the file object (if it has one), otherwise
use 'rb'.
The documentation should still show this as required until
there's a new release.
ExtensionClasses in isinstance() and issubclass().
- abstract instance and class protocols are used *only* in those
cases that would generate errors before the patch. That is, there's
no penalty for the normal case.
- instance protocol: an object smells like an instance if it
has a __class__ attribute that smells like a class.
- class protocol: an object smells like a class if it has a
__bases__ attribute that is a tuple with elements that
smell like classes (although not all elements may actually get
sniffed ;).
Added support for unseekable files.
(I use unqualified excepts since we don't know why the seek/tell might
fail. In my case it was because of an AttributeError.)
Fred Drake
Jack Jansen
Just van Rossum
Guido van Rossum