为什么会出现错误“表达式不可接受”？

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(a > b) ? c = 10 : (a < b) ? c = 20 : c = 30;

为什么此代码会产生一个错误，称为“表达式不可接受”？

错误消息说“ c = 30”，这部分导致了错误。

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  • dquis
    dquis 回复

    Because ternary operator ?: has precedence over =, the expression is parsed as:

    ((a > b) ? c = 10 : (a < b) ? c = 20 : c) = 30;

    Because you can't "assign" to (a > b) ? c = 10 : (a < b) ? c = 20 : c, your compiler errors. You want:

    (a > b) ? c = 10 : (a < b) ? c = 20 : (c = 30);

    但是写起来真的更好：

    c = (a > b) ? 10 : (a < b) ? 20 : 30;