減算 (-)
BaselineWidely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
減算演算子 (-) は 2 つのオペランドの間で減算し、それらの差を生成します。
試してみましょう
console.log(5 - 3);// Expected output: 2console.log(3.5 - 5);// Expected output: -1.5console.log(5 - "hello");// Expected output: NaNconsole.log(5 - true);// Expected output: 4構文
js
x - y;例
数値の減算
js
5 - 3; // 23 - 5; // -2非数の減算
js
"foo" - 3; // NaN仕様書
| Specification |
|---|
| ECMAScript® 2026 Language Specification # sec-subtraction-operator-minus |