乗算 (*)
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
乗算演算子 (*) はオペランドの積を生成します。
試してみましょう
console.log(3 * 4); // Expected output: 12 console.log(-3 * 4); // Expected output: -12 console.log("3" * 2); // Expected output: 6 console.log("foo" * 2); // Expected output: NaN 構文
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x * y; 例
数値を用いた乗算
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2 * 2; // 4 -2 * 2; // -4 無限大との乗算
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Infinity * 0; // NaN Infinity * Infinity; // Infinity 非数との乗算
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"foo" * 2; // NaN 仕様書
| Specification |
|---|
| ECMAScript® 2026 Language Specification # sec-multiplicative-operators |
