Number.NaN
Baseline
Widely available
This feature is well established and works across many devices and browser versions. Itâs been available across browsers since 2015å¹´7æ.
Number.NaN éçãã¼ã¿ããããã£ã¯éæ° (Not-A-Number) ã表ãå¤ã§ãããNaN ã¨åãã§ããNaN ã®åä½ã«ã¤ãã¦ã®è©³ããæ
å ±ã¯ãã°ãã¼ãã«ããããã£ã®èª¬æãåç
§ãã¦ãã ããã
試ãã¦ã¿ã¾ããã
function clean(x) {
if (x === Number.NaN) {
// true ã«ãªããã¨ã¯ãªã
return null;
}
if (isNaN(x)) {
return 0;
}
}
console.log(clean(Number.NaN));
// äºæ³ãããçµæ: 0
å¤
æ°å¤ NaN ã§ãã
Number.NaN ã®ããããã£å±æ§ | |
|---|---|
| æ¸è¾¼å¯è½ | ä¸å¯ |
| åæå¯è½ | ä¸å¯ |
| è¨å®å¯è½ | ä¸å¯ |
解説
NaN 㯠Number ã®éçããããã£ã§ãã®ã§ãæ°å¤ã®ããããã£ã¨ãã¦ã§ã¯ãªãã常㫠Number.NaN ã¨ãã¦ä½¿ç¨ãã¦ãã ããã
ä¾
å¤ãæ°å¤ã§ãããã©ããã®ãã§ãã¯
js
function sanitize(x) {
if (isNaN(x)) {
return Number.NaN;
}
return x;
}
ä»æ§æ¸
| Specification |
|---|
| ECMAScript® 2027 Language Specification # sec-number.nan |