executive summary:
Instead of typing 'apply(f, args, kwargs)' you can type 'f(*arg, **kwargs)'.
Some file-by-file details follow.
Grammar/Grammar:
simplify varargslist, replacing '*' '*' with '**'
add * & ** options to arglist
Include/opcode.h & Lib/dis.py:
define three new opcodes
CALL_FUNCTION_VAR
CALL_FUNCTION_KW
CALL_FUNCTION_VAR_KW
Python/ceval.c:
extend TypeError "keyword parameter redefined" message to include
the name of the offending keyword
reindent CALL_FUNCTION using four spaces
add handling of sequences and dictionaries using extend calls
fix function import_from to use PyErr_Format
The attached patch set includes a workaround to get Python with
Unicode compile on BSDI 4.x (courtesy Thomas Wouters; the cause
is a bug in the BSDI wchar.h header file) and Python interfaces
for the MBCS codec donated by Mark Hammond.
Also included are some minor corrections w/r to the docs of
the new "es" and "es#" parser markers (use PyMem_Free() instead
of free(); thanks to Mark Hammond for finding these).
The unicodedata tests are now in a separate file
(test_unicodedata.py) to avoid problems if the module cannot
be found.
/* More standard operations (at end for binary compatibility) */
should now be:
/* More standard operations (here for binary compatibility) */
since they're no longer at the end!
Attached you find an update of the Unicode implementation.
The patch is against the current CVS version. I would appreciate
if someone with CVS checkin permissions could check the changes
in.
The patch contains all bugs and patches sent this week and also
fixes a leak in the codecs code and a bug in the free list code
for Unicode objects (which only shows up when compiling Python
with Py_DEBUG; thanks to MarkH for spotting this one).
Added wrapping macros to dictobject.c, listobject.c, tupleobject.c,
frameobject.c, traceback.c that safely prevends core dumps
on stack overflow. Macros and functions in object.c, object.h.
The method is an "elevator destructor" that turns cascading
deletes into tail recursive behavior when some limit is hit.
a new proc type (objobjproc), a new slot sq_contains to
PySequenceMethods, and a new flag Py_TPFLAGS_HAVE_SEQUENCE_IN to
Py_TPFLAGS_DEFAULT. More to follow.
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.]
indicate to those that are using the CVS access that they are using a
newer-than-1.2.5 version, without committing to a particular version
number or patch level.
PycStringIO_IMPORT. While arguably the name used in the documentation
is more consistent, I think it's probably safer not to change the
macro definition and instead fix the doco.
Add a new member to the PyBufferProcs struct, bf_getcharbuffer. For
backward compatibility, this member should only be used (this includes
testing for NULL!) when the flag Py_TPFLAGS_HAVE_GETCHARBUFFER is set
in the type structure, below. Note that if its flag is not set, we
may be looking at an extension module compiled for 1.5.1, which will
have garbage at the bf_getcharbuffer member (because the struct wasn't
as long then). If the flag is one, the pointer may still be NULL.
The function found at this member is used in a similar manner as
bf_getreadbuffer, but it is known to point to 8-bit character data.
(See discussion in getargs.c checked in later.)
As a general feature for extending the type structure and the various
structures that (may) hang off it in a backwards compatible way, we
rename the tp_xxx4 "spare" slot to tp_flags. In 1.5.1 and before,
this slot was always zero. In 1.5.1, it may contain various flags
indicating extra fields that weren't present in 1.5.1. The only flag
defined so far is for the bf_getcharbuffer member of the PyBufferProcs
struct.
Note that the new spares (tp_xxx5 - tp_xxx8), once they become used,
should also be protected by a flag (or flags) in tp_flags.
The MS compiler doesn't call it 'long long', it uses __int64,
so a new #define, LONG_LONG, has been added and all occurrences
of 'long long' are replaced with it.
clear_carefully() used to do in import.c. Differences: leave only
__builtins__ alone in the 2nd pass; and don't clear the dictionary (on
the theory that as long as there are references left to the
dictionary, those might be destructors that might expect __builtins__
to be alive when they run; and __builtins__ can't normally be part of
a cycle).
embedders to force a different PYTHONHOME.
- Add new interface PyErr_PrintEx(flag); same as PyErr_Print() but
flag determines whether sys.last_* are set or not. PyErr_Print()
now simply calls PyErr_PrintEx(1).
signal handlers in a fork()ed child process when Python is compiled with
thread support. The bug was reported by Scott <scott@chronis.icgroup.com>.
What happens is that after a fork(), the variables used by the signal
module to determine whether this is the main thread or not are bogus,
and it decides that no thread is the main thread, so no signals will
be delivered.
The solution is the addition of PyOS_AfterFork(), which fixes the signal
module's variables. A dummy version of the function is present in the
intrcheck.c source file which is linked when the signal module is not
used.
is like PyImport_ImporModule(name) but receives the globals and locals
dict and the fromlist arguments as well. (The name is a char*; the
others are PyObject*s).
PyExc_NumberError, and PyExc_LookupError. Also added extern for
pre-instantiated exception instance PyExc_MemoryErrorInst.
Removed extern of obsolete exception PyExc_AccessError.
- int PyErr_GivenExceptionMatches(obj1, obj2)
Returns 1 if obj1 and obj2 are the same object, or if obj1 is an
instance of type obj2, or of a class derived from obj2
- int PyErr_ExceptionMatches(obj)
Higher level wrapper around PyErr_GivenExceptionMatches() which uses
PyErr_Occurred() as obj1. This will be the more commonly called
function.
- void PyErr_NormalizeException(typeptr, valptr, tbptr)
Normalizes exceptions, and places the normalized values in the
arguments. If type is not a class, this does nothing. If type is a
class, then it makes sure that value is an instance of the class by:
1. if instance is of the type, or a class derived from type, it does
nothing.
2. otherwise it instantiates the class, using the value as an
argument. If value is None, it uses an empty arg tuple, and if
the value is a tuple, it uses just that.
Py_DECREF, to reduce the warnings when compiling with reference count
debugging on. (There are still warnings for each call to
_Py_NewReference -- too bad.)
Introduce truly separate (sub)interpreter objects. For now, these
must be used by separate threads, created from C. See Demo/pysvr for
an example of how to use this. This also rationalizes Python's
initialization and finalization behavior:
Py_Initialize() -- initialize the whole interpreter
Py_Finalize() -- finalize the whole interpreter
tstate = Py_NewInterpreter() -- create a new (sub)interpreter
Py_EndInterpreter(tstate) -- delete a new (sub)interpreter
There are also new interfaces relating to threads and the interpreter
lock, which can be used to create new threads, and sometimes have to
be used to manipulate the interpreter lock when creating or deleting
sub-interpreters. These are only defined when WITH_THREAD is defined:
PyEval_AcquireLock() -- acquire the interpreter lock
PyEval_ReleaseLock() -- release the interpreter lock
PyEval_AcquireThread(tstate) -- acquire the lock and make the thread current
PyEval_ReleaseThread(tstate) -- release the lock and make NULL current
Other administrative changes:
- The header file bltinmodule.h is deleted.
- The init functions for Import, Sys and Builtin are now internal and
declared in pythonrun.h.
- Py_Setup() and Py_Cleanup() are no longer declared.
- The interpreter state and thread state structures are now linked
together in a chain (the chain of interpreters is a static variable
in pythonrun.c).
- Some members of the interpreter and thread structures have new,
shorter, more consistent, names.
- Added declarations for _PyImport_{Find,Fixup}Extension() to import.h.
PyThreadState pointer instead of a (frame) PyObject pointer. This
makes much more sense. It is backward incompatible, but that's no
problem, because (a) the heaviest users are the Py_{BEGIN,END}_
ALLOW_THREADS macros here, which have been fixed too; (b) there are
very few direct users; (c) those who use it are there will probably
appreciate the change.
Also, added new functions PyEval_AcquireThread() and
PyEval_ReleaseThread() which allows the threads created by the thread
module as well threads created by others (!) to set/reset the current
thread, and at the same time acquire/release the interpreter lock.
Much saner.
last variable to which a floating point expression is assigned. The
macro passes its address to a dummy function so that the optimizer
can't delay calculating its value until after the macro.
hash value. Interning strings (which requires hash caching) tries to
ensure that only one string object with a given value exists, so
equality tests are one pointer comparison. Together, these can speed
the interpreter up by as much as 20%. Each costs the size of a long
or pointer per string object. In addition, interned strings live
until the end of times. If you are concerned about memory footprint,
simply comment the #define out here (and rebuild everything!).
be Ellipsis!).
Bumped the API version because a linker-visible symbol is affected.
Old C code will still compile -- there's a b/w compat macro.
Similarly, old Python code will still run, builtin exports both
Ellipses and Ellipsis.
Under Windows, add MS_DLL_ID and MS_DLL_VERSION_ID for Mark H.
Independent change: if Py_TRACE_REFS is defined, rename Py_InitModule4
so so linking with incompatible modules will create a link time error.
[Backing out of previous changes (also for modsupport.c) to test
the latter at runtime.]
Guido van Rossum
Jeremy Hylton
Fred Drake
Barry Warsaw