initialization of class exceptions. Specifically:
init_class_exc(): This function now returns an integer status of the
class exception initialization. No fatal errors in this method now.
Also, use PySys_WriteStderr() when writing error messages. When an
error occurs in this function, 0 is returned, but the partial creation
of the exception classes is not undone (this happens elsewhere).
Things that could trigger the fallback:
- exceptions.py fails to be imported (due to syntax error, etc.)
- one of the exception classes is missing (e.g. due to library
version mismatch)
- exception class can't be inserted into __builtin__'s dictionary
- MemoryError instance can't be pre-allocated
- some other PyErr_Occurred
newstdexception(): Changed the error message. This is still a fatal
error because if the string based exceptions can't be created, we
really can't continue.
initerrors(): Be sure to xdecref the .exc field, which might be
non-NULL if class exceptions init was aborted.
_PyBuiltin_Init_2(): If class exception init fails, print a warning
message and reinstate the string based exceptions.
OSError. The EnvironmentError serves primarily as the (common
implementation) base class for IOError and OSError. OSError is used
by posixmodule.c
Also added tuple definition of EnvironmentError when using string
based exceptions.
(1) If a sequence S is shorter than len(S) indicated, don't fail --
just use the shorter size. (I.e, len(S) is just a hint.)
(2) Implement the special case map(None, S) as list(S) -- it's faster.
the code here becomes much simpler. In particular: abs(), divmod(),
pow(), int(), long(), float(), len(), tuple(), list().
Also make sure that no use of a function pointer gotten from a
tp_as_sequence or tp_as_mapping structure is made without checking it
for NULL first.
A few other cosmetic things, such as properly reindenting slice().
but annoying memory leak. This was introduced when PyExc_Exception
was added; the loop above populating the PyExc_StandardError exception
tuple started at index 1 in bltin_exc, but PyExc_Exception was added
at index 0, so PyExc_StandardError was getting inserted in itself!
How else can a tuple include itself?!
Change the loop to start at index 2.
This was a *fun* one! :-)
