如果评估,则更喜欢

Question

哪个是首选方法？假设myInteger 99.99%的时间将具有有效值,并且此方法将被非常快速地调用.

-(BOOL)validDate
{
    NSUInteger myInteger = ...//method to obtain value;    
    if (myInteger != NSNotFound)
        return YES;        
    return NO;
}


-(BOOL)validDate
{
    NSUInteger myInteger = ...//method to obtain value;    
    if (myInteger == NSNotFound)
        return NO;        
    return YES;
}

Answer 1

首选的是:

- (BOOL)validDate
{
    NSUInteger myInteger = ...//method to obtain value;    

    return (myInteger != NSNotFound);
}

因为它实际上不需要执行分支.

请注意,除非您运行此代码很多,否则差异将会不知不觉地变小......