try和finally的return问题

2018-10-04

先来看一个代码片段

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try{
    return true;
}finally{
    return false;
}

问最后的结果是true还是false，答案是false。下面改造一下代码片段，来看一下整个顺序流程。

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const num = 0;

tryReturn = () => {
    console.log('我是try return');
    ++num;
    console.log(num);
    return ++num;
}

finallyReturn = () =>{
    console.log('我是finally return');
    return ++num;
}

test = () => {
    try{
        console.log('我是try块');
        return tryReturn();
    }finally{
        console.log('我是finally块');
        return finallyReturn();
    }
}