Big Hammer to implement -Qnew as PEP 238 says it should work (a global
option affecting all instances of "/").
pydebug.h, main.c, pythonrun.c: define a private _Py_QnewFlag flag, true
iff -Qnew is passed on the command line. This should go away (as the
comments say) when true division becomes The Rule. This is
deliberately not exposed to runtime inspection or modification: it's
a one-way one-shot switch to pretend you're using Python 3.
ceval.c: when _Py_QnewFlag is set, treat BINARY_DIVIDE as
BINARY_TRUE_DIVIDE.
test_{descr, generators, zipfile}.py: fiddle so these pass under
-Qnew too. This was just a matter of s!/!//! in test_generators and
test_zipfile. test_descr was trickier, as testbinop() is passed
assumptions that "/" is the same as calling a "__div__" method; put
a temporary hack there to call "__truediv__" instead when the method
name is "__div__" and 1/2 evaluates to 0.5.
Three standard tests still fail under -Qnew (on Windows; somebody
please try the Linux tests with -Qnew too! Linux runs a whole bunch
of tests Windows doesn't):
test_augassign
test_class
test_coercion
I can't stay awake longer to stare at this (be my guest). Offhand
cures weren't obvious, nor was it even obvious that cures are possible
without major hackery.
Question: when -Qnew is in effect, should calls to __div__ magically
change into calls to __truediv__? See "major hackery" at tail end of
last paragraph <wink>.
PEP 238. Changes:
- add a new flag variable Py_DivisionWarningFlag, declared in
pydebug.h, defined in object.c, set in main.c, and used in
{int,long,float,complex}object.c. When this flag is set, the
classic division operator issues a DeprecationWarning message.
- add a new API PyRun_SimpleStringFlags() to match
PyRun_SimpleString(). The main() function calls this so that
commands run with -c can also benefit from -Dnew.
- While I was at it, I changed the usage message in main() somewhat:
alphabetized the options, split it in *four* parts to fit in under
512 bytes (not that I still believe this is necessary -- doc strings
elsewhere are much longer), and perhaps most visibly, don't display
the full list of options on each command line error. Instead, the
full list is only displayed when -h is used, and otherwise a brief
reminder of -h is displayed. When -h is used, write to stdout so
that you can do `python -h | more'.
Notes:
- I don't want to use the -W option to control whether the classic
division warning is issued or not, because the machinery to decide
whether to display the warning or not is very expensive (it involves
calling into the warnings.py module). You can use -Werror to turn
the warnings into exceptions though.
- The -Dnew option doesn't select future division for all of the
program -- only for the __main__ module. I don't know if I'll ever
change this -- it would require changes to the .pyc file magic
number to do it right, and a more global notion of compiler flags.
- You can usefully combine -Dwarn and -Dnew: this gives the __main__
module new division, and warns about classic division everywhere
else.
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.
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.
the internal API function to release the interned strings as the very
last thing before returning status. This aids in memory use debugging
because it eliminates a huge source of noise from the reports. This
is never called during normal (non-debugging) use because releasing
the interned strings slows Python's shutdown and isn't necessary
anyway because the system will always reclaim the memory.
regardless of whether the system getopt() does what we want. This avoids the
hassle with prototypes and externs, and the check to see if the system
getopt() does what we want. Prefix optind, optarg and opterr with _PyOS_ to
avoid name clashes. Add new include file to define the right symbols. Fix
Demo/pyserv/pyserv.c to include getopt.h itself, instead of relying on
Python to provide it.
PyRun_FileEx(). These are the same as their non-Ex counterparts but
have an extra argument, a flag telling them to close the file when
done.
Then this is used by Py_Main() and execfile() to close the file after
it is parsed but before it is executed.
Adding APIs seems strange given the feature freeze but it's the only
way I see to close the bug report without incompatible changes.
[ Bug #110616 ] source file stays open after parsing is done (PR#209)
up the _tkinter main loop. Not clear why; the _kbhit() call _tkinter
makes probably confuses the stdio library when buffering isn't set to
whatever it is by default.
- New option -x, to skip first line of script
- Use the correct platform-specific delimiter and library location in
the usage message
(Also removed two blank lines and moved one line around so that each
part of the usage message is again under 512 bytes and the whole usage
message still fits in 23 lines.)
it can be placed in the library.
Other, related changes:
- Moved the inspection of some environment variables to
Py_Initialize().
- Got rid of -s option.
- Moved Py_GetProgramName() and related logic to pythonrun.c; call
Py_SetProgramName() instead.
- Print the version header *after* successful initialization.
This used to be done whenever stdin was interactive. Now we only do
it when the -i flag is given. Also (and this is the real reason for
this fix) we explicitly allocate a buffer -- this seems to be
necessary on Windows.
Tim Peters
Guido van Rossum
Neil Schemenauer
Marc-André Lemburg
Jeremy Hylton
Barry Warsaw
Thomas Wouters
Fredrik Lundh