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  • 1. JavascriptTips and Tricks
    @EBvi
  • 2. Declaring a Function
    function foo() {}
    var bar = function() {}
    The difference is that foo is defined at parse-time for a script block, whereas bar is defined at run-time.
  • 3. Anonymous function
    (function (){})
  • 4. Different ways of calling functions
    alert (“Hello, World!");
    (alert) (“Hello, World!");
    (function(x,y,z) {return (x+y+z)}) (1, 2, 3);
  • 5. Using functional concepts
    Functions need not have names all the time.
    Functions can be assigned to variables like other values.
    A function expression can be written and enclosed in parentheses for application later.
    Functions can be passed as arguments to other functions.
  • 6. JS does not have block scope.
    varx = 1;
    {
      var x = 2;
    }
    alert(x); // outputs 2
    Block statements do not introduce a scope.
  • 7. {}
    {} is object notation in JavaScript.
    An extremely terse and flexible way to pass information.
  • 8. ;
    At the end of the last script without a ; on the end. If you have a ; at the start on yours, it's safe.
  • 9. ++ and --
    The ++ (increment) and -- (decrement) operators have been known to contribute to bad code by encouraging excessive trickiness. They are second only to faulty architecture in enabling to viruses and other security menaces. There is a plusplus option that prohibits the use of these operators.
    - Douglas Crockford
  • 10. use === and !== instead of == and !=
    == is not transitive. If you use === it would give false for all of these statements as expected.
  • 11. Reference
    http://stackoverflow.com/questions
    http://en.wikipedia.org/wiki/Unobtrusive_JavaScript
    http://javascript.crockford.com
    http://www.ibm.com/developerworks/library/wa-javascript.html
    https://developer.mozilla.org/en/Core_JavaScript_1.5_Guide/Statements
    JavaScript: The Good Parts