<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8" />
    <title>Document</title>
  </head>
  <body>
    <script type="text/javascript" >
      /* function sum(a,b,c){
        return a+b+c
      } */

      function sum(a){
        return(b)=>{
          return (c)=>{
            return a+b+c
          }
        }
      }
      const result = sum(1)(2)(3)
      console.log(result);
    </script>
  </body>
</html>

reactjs基础知识：演示函数的柯里化_javascript