Scala鐨勮В閲婂櫒鍦ㄨВ鏋愬嚱鏁板弬鏁?function arguments)鏃舵湁涓ょ鏂瑰紡錛?/p>
- 浼犲艱皟鐢紙call-by-value錛夛細鍏堣綆楀弬鏁拌〃杈懼紡鐨勫鹼紝鍐嶅簲鐢ㄥ埌鍑芥暟鍐呴儴錛?/li>
- 浼犲悕璋冪敤錛坈all-by-name錛夛細灝嗘湭璁＄畻鐨勫弬鏁拌〃杈懼紡鐩存帴搴旂敤鍒板嚱鏁板唴閮?/li>
鍦ㄨ繘鍏ュ嚱鏁板唴閮ㄥ墠錛屼紶鍊艱皟鐢ㄦ柟寮忓氨宸茬粡灝嗗弬鏁拌〃杈懼紡鐨勫艱綆楀畬姣曪紝鑰屼紶鍚嶈皟鐢ㄦ槸鍦ㄥ嚱鏁板唴閮ㄨ繘琛屽弬鏁拌〃杈懼紡鐨勫艱綆楃殑銆?/p>
榪欏氨閫犳垚浜嗕竴縐嶇幇璞★紝姣忔浣跨敤浼犲悕璋冪敤鏃訛紝瑙ｉ噴鍣ㄩ兘浼氳綆椾竴嬈¤〃杈懼紡鐨勫箋?/p>
object Test { def main(args: Array[String]) { delayed(time()); } def time() = { println("鑾峰彇鏃墮棿錛屽崟浣嶄負綰崇") System.nanoTime } def delayed( t: => Long ) = { println("鍦?delayed 鏂規硶鍐?) println("鍙傛暟錛?" + t) t } }
浠ヤ笂瀹炰緥涓垜浠０鏄庝簡 delayed 鏂規硶錛?璇ユ柟娉曞湪鍙橀噺鍚嶅拰鍙橀噺綾誨瀷浣跨敤 => 絎﹀彿鏉ヨ緗紶鍚嶈皟鐢ㄣ傛墽琛屼互涓婁唬鐮侊紝杈撳嚭緇撴灉濡備笅錛?/p>
$ scalac Test.scala $ scala Test 鍦?/span> delayed 鏂規硶鍐?/span> 鑾峰彇鏃墮棿錛屽崟浣嶄負綰崇 鍙傛暟錛?/span> 241550840475831 鑾峰彇鏃墮棿錛屽崟浣嶄負綰崇
瀹炰緥涓?delay 鏂規硶鎵撳嵃浜嗕竴鏉′俊鎭〃紺鴻繘鍏ヤ簡璇ユ柟娉曪紝鎺ョ潃 delay 鏂規硶鎵撳嵃鎺ユ敹鍒扮殑鍊鹼紝鏈鍚庡啀榪斿洖 t銆?/p>
jinfeng_wang 2016-12-16 11:42 鍙戣〃璇勮
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