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"======================================================================
|
| True Method Definitions
|
|
======================================================================"
"======================================================================
|
| Copyright 1988,92,94,95,99,2000,2001
| 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.LIB.
| If not, write to the Free Software Foundation, 59 Temple Place - Suite
| 330, Boston, MA 02110-1301, USA.
|
======================================================================"
Boolean subclass: True [
| truthValue |
<category: 'Language-Data types'>
<comment: 'I represent truth and justice in the world. My motto is "semper veritatis".'>
asCBooleanValue [
<category: 'C hacks'>
^1
]
ifTrue: trueBlock ifFalse: falseBlock [
"We are true -- evaluate trueBlock"
<category: 'basic'>
^trueBlock value
]
ifFalse: falseBlock ifTrue: trueBlock [
"We are true -- evaluate trueBlock"
<category: 'basic'>
^trueBlock value
]
ifTrue: trueBlock [
"We are true -- evaluate trueBlock"
<category: 'basic'>
^trueBlock value
]
ifFalse: falseBlock [
"We are true -- answer nil"
<category: 'basic'>
^nil
]
not [
"We are true -- answer false"
<category: 'basic'>
^false
]
& aBoolean [
"We are true -- anded with anything, we always answer the other operand"
<category: 'basic'>
^aBoolean
]
| aBoolean [
"We are true -- ored with anything, we always answer true"
<category: 'basic'>
^true
]
eqv: aBoolean [
"Answer whether the receiver and aBoolean represent the
same boolean value"
<category: 'basic'>
^aBoolean
]
xor: aBoolean [
"Answer whether the receiver and aBoolean represent different
boolean values"
<category: 'basic'>
^aBoolean not
]
and: aBlock [
"We are true -- anded with anything, we always answer the other operand,
so evaluate aBlock"
<category: 'basic'>
^aBlock value
]
or: aBlock [
"We are true -- ored with anything, we always answer true"
<category: 'basic'>
^true
]
printOn: aStream [
"Print a representation of the receiver on aStream"
<category: 'printing'>
aStream nextPutAll: 'true'
]
]