with an indented code block but no newline would raise SyntaxError.
This would have been a four-line change in parsetok.c... Except
codeop.py depends on this behavior, so a compilation flag had to be
invented that causes the tokenizer to revert to the old behavior;
this required extra changes to 2 .h files, 2 .c files, and 2 .py
files. (Fixes SF bug #501622.)
object is not a real str or unicode but an instance
of a subclass, construct the output via looping
over __getitem__. This guarantees that the result
is the same for function==None and function==lambda x:x
This doesn't happen for tuples, because filtertuple()
uses PyTuple_GetItem().
(This was discussed on SF bug #665835).
blindly assumed that tp_as_sequence->sq_item always returns
a str or unicode object. This might fail with str or unicode
subclasses.
This patch checks whether the object returned from __getitem__
is a str/unicode object and raises a TypeError if not (and
the filter function returned true).
Furthermore the result for __getitem__ can be more than one
character long, so checks for enough memory have to be done.
Obtain cleaner coding and a system wide
performance boost by using the fast, pre-parsed
PyArg_Unpack function instead of PyArg_ParseTuple
function which is driven by a format string.
supported as the second argument. This has the same meaning as
for isinstance(), i.e. issubclass(X, (A, B)) is equivalent
to issubclass(X, A) or issubclass(X, B). Compared to isinstance(),
this patch does not search the tuple recursively for classes, i.e.
any entry in the tuple that is not a class, will result in a
TypeError.
This closes SF patch #649608.
- Use PyObject_Call() instead of PyEval_CallObject(), saves several
layers of calls and checks.
- Pre-allocate the argument tuple rather than calling Py_BuildValue()
each time round the loop.
- For filter(None, seq), avoid an INCREF and a DECREF.
These built-in functions are replaced by their (now callable) type:
slice()
buffer()
and these types can also be called (but have no built-in named
function named after them)
classobj (type name used to be "class")
code
function
instance
instancemethod (type name used to be "instance method")
The module "new" has been replaced with a small backward compatibility
placeholder in Python.
A large portion of the patch simply removes the new module from
various platform-specific build recipes. The following binary Mac
project files still have references to it:
Mac/Build/PythonCore.mcp
Mac/Build/PythonStandSmall.mcp
Mac/Build/PythonStandalone.mcp
[I've tweaked the code layout and the doc strings here and there, and
added a comment to types.py about StringTypes vs. basestring. --Guido]
for 'str' and 'unicode', and can be used instead of
types.StringTypes, e.g. to test whether something is "a string":
isinstance(x, string) is True for Unicode and 8-bit strings. This
is an abstract base class and cannot be instantiated directly.
don't understand how this function works, also beefed up the docs. The
most common usage error is of this form (often spread out across gotos):
if (_PyString_Resize(&s, n) < 0) {
Py_DECREF(s);
s = NULL;
goto outtahere;
}
The error is that if _PyString_Resize runs out of memory, it automatically
decrefs the input string object s (which also deallocates it, since its
refcount must be 1 upon entry), and sets s to NULL. So if the "if"
branch ever triggers, it's an error to call Py_DECREF(s): s is already
NULL! A correct way to write the above is the simpler (and intended)
if (_PyString_Resize(&s, n) < 0)
goto outtahere;
Bugfix candidate.
Highlights: import and friends will understand any of \r, \n and \r\n
as end of line. Python file input will do the same if you use mode 'U'.
Everything can be disabled by configuring with --without-universal-newlines.
See PEP278 for details.
PEP 285. Everything described in the PEP is here, and there is even
some documentation. I had to fix 12 unit tests; all but one of these
were printing Boolean outcomes that changed from 0/1 to False/True.
(The exception is test_unicode.py, which did a type(x) == type(y)
style comparison. I could've fixed that with a single line using
issubtype(x, type(y)), but instead chose to be explicit about those
places where a bool is expected.
Still to do: perhaps more documentation; change standard library
modules to return False/True from predicates.
Based on the patch from Danny Yoo. The fix is in exec_statement() in
ceval.c.
There are also changes to introduce use of PyCode_GetNumFree() in
several places.
of PyMapping_Keys because we know we have a real dict. Tolerate that
objects may have an attr named "__dict__" that's not a dict (Py_None
popped up during testing).
test_descr.py, test_dir(): Test the new classic-class behavior; beef up
the new-style class test similarly.
test_pyclbr.py, checkModule(): dir(C) is no longer a synonym for
C.__dict__.keys() when C is a classic class (looks like the same thing
that burned distutils! -- should it be *made* a synoym again? Then it
would be inconsistent with new-style class behavior.).
bag. It's clearly wrong for classic classes, at heart because a classic
class doesn't have a __class__ attribute, and I'm unclear on whether
that's feature or bug. I'll repair this once I find out (in the
meantime, dir() applied to classic classes won't find the base classes,
while dir() applied to a classic-class instance *will* find the base
classes but not *their* base classes).
Please give the new dir() a try and see whether you love it or hate it.
The new dir([]) behavior is something I could come to love. Here's
something to hate:
>>> class C:
... pass
...
>>> c = C()
>>> dir(c)
['__doc__', '__module__']
>>>
The idea that an instance has a __doc__ attribute is jarring (of course
it's really c.__class__.__doc__ == C.__doc__; likewise for __module__).
OTOH, the code already has too many special cases, and dir(x) doesn't
have a compelling or clear purpose when x isn't a module.
builtin_eval wasn't merging in the compiler flags from the current frame;
I suppose we never noticed this before because future division is the
first future-feature that can affect expressions (nested_scopes and
generators had only statement-level effects).
- Do not compile unicodeobject, unicodectype, and unicodedata if Unicode is disabled
- check for Py_USING_UNICODE in all places that use Unicode functions
- disables unicode literals, and the builtin functions
- add the types.StringTypes list
- remove Unicode literals from most tests.
Fix suggested by Michael Hudson: Raise TypeError if attribute name
passed to getattr() is not a string or Unicode. There is some
unfortunate duplication of code between builtin_getattr() and
PyObject_GetAttr(), but it appears to be unavoidable.
that info to code dynamically compiled *by* code compiled with generators
enabled. Doesn't yet work because there's still no way to tell the parser
that "yield" is OK (unlike nested_scopes, the parser has its fingers in
this too).
Replaced PyEval_GetNestedScopes by a more-general
PyEval_MergeCompilerFlags. Perhaps I should not have? I doubted it was
*intended* to be part of the public API, so just did.
- the correct range for the error message is range(0x110000);
- put the 4-byte Unicode-size code inside the same else branch as the
2-byte code, rather generating unreachable code in the 2-byte case.
- Don't hide the 'else' behine the '}'.
(I would prefer that in 4-byte mode, any value should be accepted, but
reasonable people can argue about that, so I'll put that off.)
Add configure option --enable-unicode.
Add config.h macros Py_USING_UNICODE, PY_UNICODE_TYPE, Py_UNICODE_SIZE,
SIZEOF_WCHAR_T.
Define Py_UCS2.
Encode and decode large UTF-8 characters into single Py_UNICODE values
for wide Unicode types; likewise for UTF-16.
Remove test whether sizeof Py_UNICODE is two.
NEEDS DOC CHANGES.
More AttributeErrors transmuted into TypeErrors, in test_b2.py, and,
again, this strikes me as a good thing.
This checkin completes the iterator generalization work that obviously
needed to be done. Can anyone think of others that should be changed?
NEEDS DOC CHANGES.
Possibly contentious: The first time s.next() yields StopIteration (for
a given map argument s) is the last time map() *tries* s.next(). That
is, if other sequence args are longer, s will never again contribute
anything but None values to the result, even if trying s.next() again
could yield another result. This is the same behavior map() used to have
wrt IndexError, so it's the only way to be wholly backward-compatible.
I'm not a fan of letting StopIteration mean "try again later" anyway.
Also a 2.1 bugfix candidate (am I supposed to do something with those?).
Took away map()'s insistence that sequences support __len__, and cleaned
up the convoluted code that made it *look* like it really cared about
__len__ (in fact the old ->len field was only *used* as a flag bit, as
the main loop only looked at its sign bit, setting the field to -1 when
IndexError got raised; renamed the field to ->saw_IndexError instead).
new slot tp_iter in type object, plus new flag Py_TPFLAGS_HAVE_ITER
new C API PyObject_GetIter(), calls tp_iter
new builtin iter(), with two forms: iter(obj), and iter(function, sentinel)
new internal object types iterobject and calliterobject
new exception StopIteration
new opcodes for "for" loops, GET_ITER and FOR_ITER (also supported by dis.py)
new magic number for .pyc files
new special method for instances: __iter__() returns an iterator
iteration over dictionaries: "for x in dict" iterates over the keys
iteration over files: "for x in file" iterates over lines
TODO:
documentation
test suite
decide whether to use a different way to spell iter(function, sentinal)
decide whether "for key in dict" is a good idea
use iterators in map/filter/reduce, min/max, and elsewhere (in/not in?)
speed tuning (make next() a slot tp_next???)
Jeffery Collins pointed out that filterstring decrefs a character object
before it's done using it. This works by accident today because another
module always happens to have an active reference too at the time. The
accident doesn't work after his Pippy modifications, and since it *is*
an accident even in the mainline Python, it should work by design there too.
The patch accomplishes that.
If a module has a future statement enabling nested scopes, they are
also enable for the exec statement and the functions compile() and
execfile() if they occur in the module.
If Python is run with the -i option, which enters interactive mode
after executing a script, and the script it runs enables nested
scopes, they are also enabled in interactive mode.
XXX The use of -i with -c "from __future__ import nested_scopes" is
not supported. What's the point?
To support these changes, many function variants have been added to
pythonrun.c. All the variants names end with Flags and they take an
extra PyCompilerFlags * argument. It is possible that this complexity
will be eliminated in a future version of the interpreter in which
nested scopes are not optional.
except that it always returns Unicode objects.
A new C API PyObject_Unicode() is also provided.
This closes patch #101664.
Written by Marc-Andre Lemburg. Copyright assigned to Guido van Rossum.
- Make error messages from issubclass() and isinstance() a bit more
descriptive (Ping, modified by Guido)
- Couple of tiny fixes to other docstrings (Ping)
- Get rid of trailing whitespace (Guido)
Neal Norwitz
Guido van Rossum
Walter Dörwald
Tim Peters
Just van Rossum
Martin v. Löwis
Raymond Hettinger
Peter Schneider-Kamp
Marc-André Lemburg
Jack Jansen
Jeremy Hylton
Thomas Wouters
Fredrik Lundh
Mark Hammond
Fred Drake
Neil Schemenauer
Andrew M. Kuchling