new Array()ã¨[]ã®é•ã„ - Qiitaconsole.log( new Array(1,2,3) ); //1,2,3 console.log( [1,2,3] ); //1,2,3 console.log( new Array(3) ); //undefined, undefined, undefined console.log( [3] ); //3 逆ã«è¨€ãˆã°ã€ new Array()ã¯[3]ã®ã‚ˆã†ã«æ•´æ•°ä¸€ã¤ã ã‘ã‚’å«ã‚€é…列を作æˆã§ããªã„ []ã¯ã‚µã‚¤ã‚ºã‚’指定ã—ã¦é…列を作æˆã§ããªã„ ã¨ã„ã†ã“ã¨ã«ãªã‚‹ã€‚ 速度é¢ã§ã®é•ã„…ã¯ã»ã¨ã‚“ã©ãªã„ å…ˆã«çµè«–を書ã„ã¦ã—ã¾ã£ãŸã€‚エンジンã«ã‚‚よるã—使ã„æ–¹ã«ã‚‚よる。ã©ã¡ã‚‰ãŒé€Ÿã„ã¨ã„ã†ã‚‚ã®ã§ã‚‚ãªã„ã®ã§ã€èªã¿ã‚„ã™ã•ã‚’優先ã™ã‚Œã°ã‚ˆã„。 完璧主義者ã®ãŸã‚ã«ã€å·®ãŒå‡ºã‚‹ãƒã‚¤ãƒ³ãƒˆã‚’ã¾ã¨ã‚ã¦ã¿ã‚‹ã€‚ å‚照解決ã®ã‚³ã‚¹ãƒˆ 「Arrayã€ã¯äºˆç´„語ã§ã¯ãªã„ã®ã§ã€ãƒãƒ¼ã‚«ãƒ«å¤‰æ•°ã‚’指ã—ã¦ã„ã‚‹å¯èƒ½æ€§ãŒã‚る。JavaScriptエン
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ã€è¿½è¨˜ï¼š2018 01/25】é…列ã®é€£çµ(concat vs Array.prototype.push.apply) - Qiita
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