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70 lines
2.1 KiB
Python
70 lines
2.1 KiB
Python
"""__future__: Record of phased-in incompatible language changes.
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Each line is of the form:
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FeatureName = "_Feature(" OptionalRelease "," MandatoryRelease) ")"
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where, normally, OptionalRelease < MandatoryRelease, and both are 5-tuples
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of the same form as sys.version_info:
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(PY_MAJOR_VERSION, # the 2 in 2.1.0a3; an int
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PY_MINOR_VERSION, # the 1; an int
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PY_MICRO_VERSION, # the 0; an int
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PY_RELEASE_LEVEL, # "alpha", "beta", "candidate" or "final"; string
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PY_RELEASE_SERIAL # the 3; an int
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)
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OptionalRelease records the first release in which
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from __future__ import FeatureName
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was accepted.
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In the case of MandatoryReleases that have not yet occurred,
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MandatoryRelease predicts the release in which the feature will become part
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of the language.
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Else MandatoryRelease records when the feature became part of the language;
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in releases at or after that, modules no longer need
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from __future__ import FeatureName
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to use the feature in question, but may continue to use such imports.
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MandatoryRelease may also be None, meaning that a planned feature got
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dropped.
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Instances of class _Feature have two corresponding methods,
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.getOptionalRelease() and .getMandatoryRelease().
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No feature line is ever to be deleted from this file.
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"""
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class _Feature:
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def __init__(self, optionalRelease, mandatoryRelease):
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self.optional = optionalRelease
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self.mandatory = mandatoryRelease
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def getOptionalRelease(self):
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"""Return first release in which this feature was recognized.
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This is a 5-tuple, of the same form as sys.version_info.
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"""
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return self.optional
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def getMandatoryRelease(self):
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"""Return release in which this feature will become mandatory.
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This is a 5-tuple, of the same form as sys.version_info, or, if
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the feature was dropped, is None.
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"""
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return self.mandatory
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def __repr__(self):
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return "Feature(" + `self.getOptionalRelease()` + ", " + \
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`self.getMandatoryRelease()` + ")"
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nested_scopes = _Feature((2, 1, 0, "beta", 1), (2, 2, 0, "final", 0))
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