1 #!/usr/bin/env python 2 3 """ 4 Operator-related functions. 5 6 Copyright (C) 2015, 2016 Paul Boddie <paul@boddie.org.uk> 7 8 This program is free software; you can redistribute it and/or modify it under 9 the terms of the GNU General Public License as published by the Free Software 10 Foundation; either version 3 of the License, or (at your option) any later 11 version. 12 13 This program is distributed in the hope that it will be useful, but WITHOUT 14 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 15 FOR A PARTICULAR PURPOSE. See the GNU General Public License for more 16 details. 17 18 You should have received a copy of the GNU General Public License along with 19 this program. If not, see <http://www.gnu.org/licenses/>. 20 """ 21 22 def _binary_op(this, other, op): 23 24 "Test the types of 'this' and 'other', performing 'op' if identical." 25 26 if this.__class__ is other.__class__: 27 return op(this, other) 28 else: 29 return NotImplemented 30 31 def _negate(result): 32 33 "Negate any valid logical value." 34 35 if result is NotImplemented: 36 return result 37 else: 38 return not result 39 40 # vim: tabstop=4 expandtab shiftwidth=4
