You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
105 lines
3.3 KiB
105 lines
3.3 KiB
14 years ago
|
"""Record of phased-in incompatible language changes.
|
||
|
|
||
|
Each line is of the form:
|
||
|
|
||
|
FeatureName = "_Feature(" OptionalRelease "," MandatoryRelease ","
|
||
|
CompilerFlag ")"
|
||
|
|
||
|
where, normally, OptionalRelease < MandatoryRelease, and both are 5-tuples
|
||
|
of the same form as sys.version_info:
|
||
|
|
||
|
(PY_MAJOR_VERSION, # the 2 in 2.1.0a3; an int
|
||
|
PY_MINOR_VERSION, # the 1; an int
|
||
|
PY_MICRO_VERSION, # the 0; an int
|
||
|
PY_RELEASE_LEVEL, # "alpha", "beta", "candidate" or "final"; string
|
||
|
PY_RELEASE_SERIAL # the 3; an int
|
||
|
)
|
||
|
|
||
|
OptionalRelease records the first release in which
|
||
|
|
||
|
from __future__ import FeatureName
|
||
|
|
||
|
was accepted.
|
||
|
|
||
|
In the case of MandatoryReleases that have not yet occurred,
|
||
|
MandatoryRelease predicts the release in which the feature will become part
|
||
|
of the language.
|
||
|
|
||
|
Else MandatoryRelease records when the feature became part of the language;
|
||
|
in releases at or after that, modules no longer need
|
||
|
|
||
|
from __future__ import FeatureName
|
||
|
|
||
|
to use the feature in question, but may continue to use such imports.
|
||
|
|
||
|
MandatoryRelease may also be None, meaning that a planned feature got
|
||
|
dropped.
|
||
|
|
||
|
Instances of class _Feature have two corresponding methods,
|
||
|
.getOptionalRelease() and .getMandatoryRelease().
|
||
|
|
||
|
CompilerFlag is the (bitfield) flag that should be passed in the fourth
|
||
|
argument to the builtin function compile() to enable the feature in
|
||
|
dynamically compiled code. This flag is stored in the .compiler_flag
|
||
|
attribute on _Future instances. These values must match the appropriate
|
||
|
#defines of CO_xxx flags in Include/compile.h.
|
||
|
|
||
|
No feature line is ever to be deleted from this file.
|
||
|
"""
|
||
|
|
||
|
all_feature_names = [
|
||
|
"nested_scopes",
|
||
|
"generators",
|
||
|
"division",
|
||
|
]
|
||
|
|
||
|
__all__ = ["all_feature_names"] + all_feature_names
|
||
|
|
||
|
# The CO_xxx symbols are defined here under the same names used by
|
||
|
# compile.h, so that an editor search will find them here. However,
|
||
|
# they're not exported in __all__, because they don't really belong to
|
||
|
# this module.
|
||
|
CO_NESTED = 0x0010 # nested_scopes
|
||
|
CO_GENERATOR_ALLOWED = 0x1000 # generators
|
||
|
CO_FUTURE_DIVISION = 0x2000 # division
|
||
|
|
||
|
class _Feature:
|
||
|
def __init__(self, optionalRelease, mandatoryRelease, compiler_flag):
|
||
|
self.optional = optionalRelease
|
||
|
self.mandatory = mandatoryRelease
|
||
|
self.compiler_flag = compiler_flag
|
||
|
|
||
|
def getOptionalRelease(self):
|
||
|
"""Return first release in which this feature was recognized.
|
||
|
|
||
|
This is a 5-tuple, of the same form as sys.version_info.
|
||
|
"""
|
||
|
|
||
|
return self.optional
|
||
|
|
||
|
def getMandatoryRelease(self):
|
||
|
"""Return release in which this feature will become mandatory.
|
||
|
|
||
|
This is a 5-tuple, of the same form as sys.version_info, or, if
|
||
|
the feature was dropped, is None.
|
||
|
"""
|
||
|
|
||
|
return self.mandatory
|
||
|
|
||
|
def __repr__(self):
|
||
|
return "_Feature" + repr((self.optional,
|
||
|
self.mandatory,
|
||
|
self.compiler_flag))
|
||
|
|
||
|
nested_scopes = _Feature((2, 1, 0, "beta", 1),
|
||
|
(2, 2, 0, "alpha", 0),
|
||
|
CO_NESTED)
|
||
|
|
||
|
generators = _Feature((2, 2, 0, "alpha", 1),
|
||
|
(2, 3, 0, "final", 0),
|
||
|
CO_GENERATOR_ALLOWED)
|
||
|
|
||
|
division = _Feature((2, 2, 0, "alpha", 2),
|
||
|
(3, 0, 0, "alpha", 0),
|
||
|
CO_FUTURE_DIVISION)
|