Skip welcome & menu and move to editor
Welcome to JS Bin
File
Add library
Share
Login or Register
Blog
Help
Load cached copy from
  • Run with JS
  • Save
  • Share
  • …
 
<!DOCTYPE html>
<html>
<head>
<meta charset=utf-8 />
<title>Strict and Loose Function#caller</title>
  <style>
    p {
      font-family: sans-serif;
      margin: 0.1em;
    }
    .err {
      color: #d00;
    }
  </style>
</head>
<body>
  <script>
    function display(msg, cls) {
        var p = document.createElement('p');
        if (cls) {
            p.className = cls;
        }
        p.innerHTML = String(msg);
        document.body.appendChild(p);
    }
​
    // The loose functions
    (function () {
      function loose1() {
        display("loose1 calling loose2");
        loose2();
      }
      loose1.id = "loose1"; // Since name isn't standard yet
      
      function loose2() {
        var c;
        
        try {
          display("loose2: looping through callers:");
          c = loose2;
          while (c) {
            display("loose2: getting " + c.id + ".caller");
            c = c.caller;
            display("loose2: got " +
                    ((c && c.id) || Object.prototype.toString.call(c)));
          }
          display("loose2: done");
        }
        catch (e) {
          display("loose2: exception: " +
                  (e.message || String(e)),
                  "err");
        }
      }
      loose2.id = "loose2";
      
      window.loose1 = loose1;
      
      window.loose2 = loose2;
    })();
    
    // The strict ones
    (function() {
      "use strict";
​
      function strict1() {
        display("strict1: calling strict2");
        strict2();
      }
      strict1.id = "strict1";
      
      function strict2() {
        display("strict2: calling loose1");
        loose1();
      }
      strict2.id = "strict2";
​
      function strict3() {
        display("strict3: calling strict4");
        strict4();
      }
      strict3.id = "strict3";
      
      function strict4() {
        var c;
        
        try {
          display("strict4: getting strict4.caller");
          c = strict4.caller;
        }
        catch (e) {
          display("strict4: exception: " +
                  (e.message || String(e)),
                 "err");
        }
      }
      strict4.id = "strict4";
      
      strict1();      
      strict3();
    })();
  </script>
</body>
</html>
​
Output

You can jump to the latest bin by adding /latest to your URL

Dismiss x
public
Bin info
anonymouspro
0viewers