Lichen

Annotated lib/__builtins__/none.py

858:8f8361de472a
2018-07-21 Paul Boddie Invocations in parameter lists may require temporary storage for contexts and accessors, but the storage locations must be different. Otherwise, the code will generate a sequence-point warning. Here, distinct ranges for parameters in lists are introduced, and accessors are now also stored in arrays, permitting distinct storage.
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#!/usr/bin/env python
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"""
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None objects.
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Copyright (C) 2015, 2016 Paul Boddie <paul@boddie.org.uk>
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This program is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free Software
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Foundation; either version 3 of the License, or (at your option) any later
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version.
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This program is distributed in the hope that it will be useful, but WITHOUT
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ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
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FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
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details.
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You should have received a copy of the GNU General Public License along with
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this program.  If not, see <http://www.gnu.org/licenses/>.
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"""
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class NoneType:
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    "The type of the None object."
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    def __bool__(self):
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        "None is always false."
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        return False
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    def __str__(self):
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        "Return a string representation."
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        return "None"
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    __repr__ = __str__
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None = NoneType()
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