javascript-patterns/function-patterns/memoization.html at master · codeinpeace/javascript-patterns · GitHub

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<!doctype html>
<html lang="en">
<head>
<title>JavaScript Patterns</title>
<meta charset="utf-8">
</head>
<body>
<script>
  var myFunc = function (param) {
    if (!myFunc.cache[param]) {
      var result = {};
      // ... expsensive operation ...
      myFunc.cache[param] = result;
    }
    return myFunc.cache[param];
  };

  // cache storage
  myFunc.cache = {};

  var myFunc = function () {
    var cachekey = JSON.stringify(Array.prototype.slice.call(arguments)),
                   result;
    if (!myFunc.cache[cachekey]) {
      result = {};
      // ... expensive operation ...
      myFunc.cache[cachekey] = result;
    }
    return myFunc.cache[cachekey];
  };

  // cache storage
  myFunc.cache = {};

  var myFunc = function (param) {
    var f = arguments.callee,
        result;
    if (!f.cache[param]) {
      result = {};
      // ... expensive operation ...
      f.cache[param] = result;
    }
    return f.cache[param];
  };

  // cache storage
  myFunc.cache = {};
</script>
</body>
</html>