lovecoding
/
VIP32


			
				
					
						
						
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    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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    <script>
        /**
         * const 特点
         * 1.去用于声明常量;
         * 2.变量名是大写的;
         * 3.不能重复声明；
         * 4.赋值不可重复修改
         * 5.不能变量提升
        */
       var a;
       const  PI = 3.14;
       const E = 2;
    //    const PI = 3.1415926;
       const Vase = 12;
       Vase = 14;
       console.log(Vase)
       console.log(A2);
       const A2 = '12';
    </script>
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