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.
- 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.
_PyImport_FixupExtension() on the exceptions module. Now
reload(exceptions) acts just like reload(sys) instead of raising
an ImportError.
This closes SF bug #422004.
Replace uses of PyCF_xxx with CO_xxx.
Replace individual feature slots in PyFutureFeatures with single
bitmask ff_features.
When flags must be transfered among the three parts of the interpreter
that care about them -- the pythonrun layer, the compiler, and the
future feature parser -- can simply or (|) the definitions.
- Add an explicit call to PyType_Ready(&PyList_Type) to pythonrun.c
(just for the heck of it, really -- we should either explicitly
ready all types, or none).
that 'yield' is a keyword. This doesn't help test_generators at all! I
don't know why not. These things do work now (and didn't before this
patch):
1. "from __future__ import generators" now works in a native shell.
2. Similarly "python -i xxx.py" now has generators enabled in the
shell if xxx.py had them enabled.
3. This program (which was my doctest proxy) works fine:
from __future__ import generators
source = """\
def f():
yield 1
"""
exec compile(source, "", "single") in globals()
print type(f())
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.
but apparently he had to go to school, so I am checking it in for him.
This makes PyRun_HandleSystemExit() a static instead, called
handle_system_exit(), and let it use the current exception rather than
passing in an exception. This slightly simplifies the code.
Update docstring and library reference section on 'sys' module.
New API PyErr_Display, just for displaying errors, called by excepthook.
Uncaught exceptions now call sys.excepthook; if that fails, we fall back
to calling PyErr_Display directly.
Also comes with sys.__excepthook__ and sys.__displayhook__.
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.
(Also remove warning about module-level global decl, because we can't
distinguish from code passed to exec.)
Define PyCompilerFlags type contains a single element,
cf_nested_scopes, that is true if a nested scopes future statement has
been entered at the interactive prompt.
New API functions:
PyNode_CompileFlags()
PyRun_InteractiveOneFlags()
-- same as their non Flags counterparts except that the take an
optional PyCompilerFlags pointer
compile.c: In jcompile() use PyCompilerFlags argument. If
cf_nested_scopes is true, compile code with nested scopes. If it
is false, but the code has a valid future nested scopes statement,
set it to true.
pythonrun.c: Create a new PyCompilerFlags object in
PyRun_InteractiveLoop() and thread it through to
PyRun_InteractiveOneFlags().
raised by the compiler.
XXX For now, text entered into the interactive intepreter is not
printed in the traceback.
Inspired by a patch from Roman Sulzhyk
compile.c:
Add helper fetch_program_text() that opens a file and reads until it
finds the specified line number. The code is a near duplicate of
similar code in traceback.c.
Modify com_error() to pass two arguments to SyntaxError constructor,
where the second argument contains the offending text when possible.
Modify set_error_location(), now used only by the symtable pass, to
set the text attribute on existing exceptions.
pythonrun.c:
Change parse_syntax_error() to continue of the offset attribute of a
SyntaxError is None. In this case, it sets offset to -1.
Move code from PyErr_PrintEx() into helper function
print_error_text(). In the helper, only print the caret for a
SyntaxError if offset > 0.
