general-patterns/single-var-pattern.html

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    <title>JavaScript Patterns</title>
    <meta charset="utf-8">
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    <script>
      /* Title: Single var Pattern
       Description: use one var statement and declare multiple variables
       */

      /* Benefits:
       * 1. Provides a single place to look for all the local variables needed by the function
       * 2. Prevents logical errors when a variable is used before it's defined
       * 3. Helps you remember to declare variables and therefore minimize globals
       * 4. Is less code (to type and to transfer over the wire)
       */

      function func() {
        var a = 1
          , b = 2
          , sum = a + b
          , myobject = {}
          , i
          , j;

        // function body...
      }

      function updateElement() {
        var el = document.getElementById("result")
          , style = el.style;
        // do something with el and style...
      }
      
      // Preferred way 
      // Move commas BEFORE vars
      // You'll not forget to add one when adding variable to the end of list
      function func() {
        var a = 1
            , b = 2
            , sum = a + b
            , myobject = {}
            , i
            , j;

        // function body...
      }

      // References
      // http://net.tutsplus.com/tutorials/javascript-ajax/the-essentials-of-writing-high-quality-javascript/
    </script>
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