TypedArray.prototype.includes()
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includes() 㯠TypedArray ã¤ã³ã¹ã¿ã³ã¹ã®ã¡ã½ããã§ãåä»ãé
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ã«ç¹å®ã®å¤ãå«ã¾ãã¦ãããã©ããã夿ãããã®çµæã«å¿ã㦠true ã false ãè¿ãã¾ãããã®ã¡ã½ãã㯠Array.prototype.includes() ã¨åãã¢ã«ã´ãªãºã ã§ãã
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const uint8 = new Uint8Array([10, 20, 30, 40, 50]);
console.log(uint8.includes(20));
// äºæ³ãããçµæ: true
// Check from position 3
console.log(uint8.includes(20, 3));
// äºæ³ãããçµæ: false
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includes(searchElement)
includes(searchElement, fromIndex)
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åï¼æå®ããå ´åã¯ã¤ã³ããã¯ã¹ fromIndex ã§ç¤ºãããåä»ãé
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ã§å¤ searchElement ãè¦ã¤ãã£ãå ´åã« true ãªãã¾ãã
解説
詳細ã«ã¤ãã¦ã¯ã Array.prototype.includes() ãã覧ãã ããããã®ã¡ã½ããã¯æ±ç¨çã§ã¯ãªããåä»ãé
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const uint8 = new Uint8Array([1, 2, 3]);
uint8.includes(2); // true
uint8.includes(4); // false
uint8.includes(3, 3); // false
// NaN ã®æ±ãï¼æµ®åå°æ°ç¹åã®é
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new Uint8Array([NaN]).includes(NaN); // false (ã³ã³ã¹ãã©ã¯ã¿ã¼ã«æ¸¡ãã NaN 㯠0 ã«å¤æããããã)
new Float32Array([NaN]).includes(NaN); // true
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| ECMAScript® 2027 Language Specification > # sec-%typedarray%.prototype.includes > |