true.st

来自「四皇后问题」· ST 代码 · 共 18 行

Class True :Boolean
[
        ifTrue: trueAlternativeBlock ifFalse: falseAlternativeBlock
                ^ trueAlternativeBlock value

!       ifFalse: falseAlternativeBlock ifTrue: trueAlternativeBlock
                ^ trueAlternativeBlock value

!       ifTrue: trueAlternativeBlock
                ^ trueAlternativeBlock value

!       ifFalse: falseAlternativeBlock
                ^ nil

|       not
                ^ false
]