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变量提升 #41

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zuopf769 opened this issue May 9, 2023 · 4 comments

zuopf769 commented May 9, 2023

// 1.
var a = 1;
if (true) {
    console.log(a);
    var a = 2;
}
// 2.
var a = 1;
if (true) {
    console.log(a);
    let a = 2;
}

Author

zuopf769 commented May 9, 2023

1，报错

Author

zuopf769 commented May 9, 2023

var a 
a = 1;
if (true) {
    console.log(a);
    a = 2;
}

Author

zuopf769 commented May 9, 2023

应该不是提升到if作用域下提升到函数作用域下

Author

zuopf769 commented May 9, 2023

第二题如果if是个function，那就是undefined了

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