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This feature is well established and works across many devices and browser versions. It’s been available across browsers since 2015年7月.
简单赋值运算符（=）用于给变量赋值。赋值表达式本身的值为要赋值的值。为了将一个值赋给多个变量，可以链式使用赋值运算符。
=
let x = 2; const y = 3; console.log(x); // Expected output: 2 console.log((x = y + 1)); // 3 + 1 // Expected output: 4 console.log((x = x * y)); // 4 * 3 // Expected output: 12
x = y
// 假设已经存在以下变量 // x = 5 // y = 10 // z = 25 x = y; // x 为 10 x = y = z; // x, y 都为 25
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