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let a = 1;
let b = 0;
a &&= 2;
console.log(a);
// Expected output: 2
b &&= 2;
console.log(b);
// Expected output: 0
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js
expr1 &&= expr2
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x && (x = y);
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js
const x = 0;
x &&= 2;
ä¹ä¸ä¼è§¦å setter 彿°ï¼
js
const x = {
get value() {
return 0;
},
set value(v) {
console.log("è°ç¨äº setter");
},
};
x.value &&= 2;
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ä¸ï¼å¦æ x ä¸ä¸ºçå¼ï¼åæ ¹æ¬ä¸ä¼å¯¹ y æ±å¼ã
js
const x = 0;
x &&= console.log("y è¿è¡äºæ±å¼");
// ä»ä¹é½ä¸ä¼è¾åº
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js
let x = 0;
let y = 1;
x &&= 0; // 0
x &&= 1; // 0
y &&= 1; // 1
y &&= 0; // 0
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