"====================================================================== | | False Method Definitions | | $Revision: 1.7.5$ | $Date: 2000/05/28 16:56:52$ | $Author: pb$ | ======================================================================" "====================================================================== | | Copyright 1988-92, 1994-95, 1999, 2000 Free Software Foundation, Inc. | Written by Steve Byrne. | | This file is part of the GNU Smalltalk class library. | | The GNU Smalltalk class library is free software; you can redistribute it | and/or modify it under the terms of the GNU Lesser General Public License | as published by the Free Software Foundation; either version 2.1, or (at | your option) any later version. | | The GNU Smalltalk class library is distributed in the hope that it will be | useful, but WITHOUT ANY WARRANTY; without even the implied warranty of | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser | General Public License for more details. | | You should have received a copy of the GNU Lesser General Public License | along with the GNU Smalltalk class library; see the file COPYING.LESSER. | If not, write to the Free Software Foundation, 59 Temple Place - Suite | 330, Boston, MA 02111-1307, USA. | ======================================================================" Boolean subclass: #False instanceVariableNames: 'truthValue' " ### What's the real ST-80 name? " classVariableNames: '' poolDictionaries: '' category: 'Language-Data types' ! False comment: 'I always tell lies. I have a single instance in the system, which represents the value false.' ! !False methodsFor: 'C hacks'! asCBooleanValue ^0 ! ! !False methodsFor: 'basic'! ifTrue: trueBlock ifFalse: falseBlock "We are false -- evaluate the falseBlock" ^falseBlock value ! ifFalse: falseBlock ifTrue: trueBlock "We are false -- evaluate the falseBlock" ^falseBlock value ! ifTrue: trueBlock "We are false -- answer nil" ^nil ! ifFalse: falseBlock "We are false -- evaluate the falseBlock" ^falseBlock value ! not "We are false -- answer true" ^true ! & aBoolean "We are false -- anded with anything, we always answer false" ^false ! | aBoolean "We are false -- ored with anything, we always answer the other operand" ^aBoolean ! eqv: aBoolean "Answer whether the receiver and aBoolean represent the same boolean value" ^aBoolean not ! xor: aBoolean "Answer whether the receiver and aBoolean represent different boolean values" ^aBoolean ! and: aBlock "We are false -- anded with anything, we always answer false" ^false ! or: aBlock "We are false -- ored with anything, we always answer the other operand, so evaluate aBlock" ^aBlock value ! ! !False methodsFor: 'printing'! printOn: aStream "Print a representation of the receiver on aStream" aStream nextPutAll: 'false' ! !