1 """Record of phased-in incompatible language changes. 2 3 Each line is of the form: 4 5 FeatureName = "_Feature(" OptionalRelease "," MandatoryRelease "," 6 CompilerFlag ")" 7 8 where, normally, OptionalRelease < MandatoryRelease, and both are 5-tuples 9 of the same form as sys.version_info: 10 11 (PY_MAJOR_VERSION, # the 2 in 2.1.0a3; an int 12 PY_MINOR_VERSION, # the 1; an int 13 PY_MICRO_VERSION, # the 0; an int 14 PY_RELEASE_LEVEL, # "alpha", "beta", "candidate" or "final"; string 15 PY_RELEASE_SERIAL # the 3; an int 16 ) 17 18 OptionalRelease records the first release in which 19 20 from __future__ import FeatureName 21 22 was accepted. 23 24 In the case of MandatoryReleases that have not yet occurred, 25 MandatoryRelease predicts the release in which the feature will become part 26 of the language. 27 28 Else MandatoryRelease records when the feature became part of the language; 29 in releases at or after that, modules no longer need 30 31 from __future__ import FeatureName 32 33 to use the feature in question, but may continue to use such imports. 34 35 MandatoryRelease may also be None, meaning that a planned feature got 36 dropped. 37 38 Instances of class _Feature have two corresponding methods, 39 .getOptionalRelease() and .getMandatoryRelease(). 40 41 CompilerFlag is the (bitfield) flag that should be passed in the fourth 42 argument to the builtin function compile() to enable the feature in 43 dynamically compiled code. This flag is stored in the .compiler_flag 44 attribute on _Future instances. These values must match the appropriate 45 #defines of CO_xxx flags in Include/compile.h. 46 47 No feature line is ever to be deleted from this file. 48 """ 49 50 all_feature_names = [ 51 "nested_scopes", 52 "generators", 53 "division", 54 "absolute_import", 55 "with_statement", 56 "print_function", 57 "unicode_literals", 58 "barry_as_FLUFL", 59 "generator_stop", 60 "annotations", 61 ] 62 63 __all__ = ["all_feature_names"] + all_feature_names 64 65 # The CO_xxx symbols are defined here under the same names defined in 66 # code.h and used by compile.h, so that an editor search will find them here. 67 # However, they're not exported in __all__, because they don't really belong to 68 # this module. 69 CO_NESTED = 0x0010 # nested_scopes 70 CO_GENERATOR_ALLOWED = 0 # generators (obsolete, was 0x1000) 71 CO_FUTURE_DIVISION = 0x20000 # division 72 CO_FUTURE_ABSOLUTE_IMPORT = 0x40000 # perform absolute imports by default 73 CO_FUTURE_WITH_STATEMENT = 0x80000 # with statement 74 CO_FUTURE_PRINT_FUNCTION = 0x100000 # print function 75 CO_FUTURE_UNICODE_LITERALS = 0x200000 # unicode string literals 76 CO_FUTURE_BARRY_AS_BDFL = 0x400000 77 CO_FUTURE_GENERATOR_STOP = 0x800000 # StopIteration becomes RuntimeError in generators 78 CO_FUTURE_ANNOTATIONS = 0x1000000 # annotations become strings at runtime 79 80 81 class _Feature: 82 83 def __init__(self, optionalRelease, mandatoryRelease, compiler_flag): 84 self.optional = optionalRelease 85 self.mandatory = mandatoryRelease 86 self.compiler_flag = compiler_flag 87 88 def getOptionalRelease(self): 89 """Return first release in which this feature was recognized. 90 91 This is a 5-tuple, of the same form as sys.version_info. 92 """ 93 return self.optional 94 95 def getMandatoryRelease(self): 96 """Return release in which this feature will become mandatory. 97 98 This is a 5-tuple, of the same form as sys.version_info, or, if 99 the feature was dropped, is None. 100 """ 101 return self.mandatory 102 103 def __repr__(self): 104 return "_Feature" + repr((self.optional, 105 self.mandatory, 106 self.compiler_flag)) 107 108 109 nested_scopes = _Feature((2, 1, 0, "beta", 1), 110 (2, 2, 0, "alpha", 0), 111 CO_NESTED) 112 113 generators = _Feature((2, 2, 0, "alpha", 1), 114 (2, 3, 0, "final", 0), 115 CO_GENERATOR_ALLOWED) 116 117 division = _Feature((2, 2, 0, "alpha", 2), 118 (3, 0, 0, "alpha", 0), 119 CO_FUTURE_DIVISION) 120 121 absolute_import = _Feature((2, 5, 0, "alpha", 1), 122 (3, 0, 0, "alpha", 0), 123 CO_FUTURE_ABSOLUTE_IMPORT) 124 125 with_statement = _Feature((2, 5, 0, "alpha", 1), 126 (2, 6, 0, "alpha", 0), 127 CO_FUTURE_WITH_STATEMENT) 128 129 print_function = _Feature((2, 6, 0, "alpha", 2), 130 (3, 0, 0, "alpha", 0), 131 CO_FUTURE_PRINT_FUNCTION) 132 133 unicode_literals = _Feature((2, 6, 0, "alpha", 2), 134 (3, 0, 0, "alpha", 0), 135 CO_FUTURE_UNICODE_LITERALS) 136 137 barry_as_FLUFL = _Feature((3, 1, 0, "alpha", 2), 138 (4, 0, 0, "alpha", 0), 139 CO_FUTURE_BARRY_AS_BDFL) 140 141 generator_stop = _Feature((3, 5, 0, "beta", 1), 142 (3, 7, 0, "alpha", 0), 143 CO_FUTURE_GENERATOR_STOP) 144 145 annotations = _Feature((3, 7, 0, "beta", 1), 146 (3, 10, 0, "alpha", 0), 147 CO_FUTURE_ANNOTATIONS) 148