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/**
STUndefinedObject.m
Wrapper for nil object
Copyright (c) 2002 Free Software Foundation
This file is part of the StepTalk project.
*/
#import "STUndefinedObject+additions.h"
#import "STBlock.h"
#import <StepTalk/STExterns.h>
#import <Foundation/NSString.h>
#import <Foundation/NSException.h>
@implementation STUndefinedObject(SmalltalkAdditions)
- (BOOL)isNil
{
return YES;
}
- ifNil:(STBlock *)block
{
return [block value];
}
- notNil:(STBlock *)block
{
return nil;
}
- ifFalse:(STBlock *)block
{
return [block value];
}
- ifTrue:(STBlock *)block
{
return nil;
}
- ifFalse:(STBlock *)block ifTrue:(STBlock *)anotherBlock
{
return [block value];
}
- ifTrue:(STBlock *)block ifFalse:(STBlock *)anotherBlock
{
return [anotherBlock value];
}
@end
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