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JavaScript OR (||) variable assignment explanation
                                
                                    (12个答案)
                                
                        
                        
                            What does the construct x = x || y mean?
                                
                                    (12个答案)
                                
                        
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我目前正在调查Three.js,并在主源文件顶部遇到了此变量声明:

var THREE = THREE || { REVISION: '52' };


我只是想知道OR(||)在这里做什么-它的功能是什么?

最佳答案

上面的意思是:

如果THREE的值计算为true,则将THREE的值分配给THREE变量,否则将其初始化为对象{ REVISION: '52' }

关于javascript - 带||的Javascript变量声明,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/13268848/

10-12 12:38
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