http:// proglit.com /

1. http://proglit.com/

2. the javascript language

3. SA BY

5. Javascript is not Java

6. Brendan Eich at Netscape in 1995 named in deal between Netscape and Sun ECMA standard calls it ECMAScript

7. only language in all modern web browsers currently focus of lots of optimization work

8. the DOM AJAX (Document Object Model, the hierarchy of objects representing page content in web browsers) (Asynchronous Javascript and XML, a technique to submit/request data without refreshing the page)

9. dynamic and (a little) functional object-oriented programming via prototyping

10. numbers booleans strings arrays (lists) objects (dictionaries) functions null

11. http://proglit.com/

12. + addition - subtraction/negation / division * multiplication % modulus

13. x * 3 + 9 ((x * 3) + 9) (+ (* x 3) 9)

14. foo(a, b, c) bar() (foo a b c) (bar)

15. foo() (foo()) (foo) foo (foo) ((foo)) foo

16. lvalue rvalue foo = bar / 2 (foo = (bar / 2)) (= foo (/ bar 2))

17. x = y = z = 4 + 2 (x = (y = (z = (4 + 2)))) (((x = y) = z) = (4 + 2)) the = operator is right-to-left associative

18. http://proglit.com/

19. x = 3; cow = 2 + x; foo(1); rat = bar();

20. free-form syntax x = 3; x=3 ; x = 3 ;

21. foo(); // ignore this /* ignore all this too */ bar();

22. /* apple /* banana orange */ lemon */

23. _foo foo_bar $foo foo$bar

24. var varname; varname = expression; var monkey; var zebra = 3;

25. undefined varjeff; foo(jeff); // OK foo(amanda); // error

26. function function(parameters) {body}

27. var helen = function(apple, orange) { return apple + orange; }; var dan = helen(3, 5);

28. ! not === equals !== not equals && and || or < less than > greater than <= less than or equal >= greater than or equal

29. !true// false !false// true !null// true !0 // true !“”// true !undefined // true

30. 3 === 3// true 3 === -2// false !true === false// true

31. (3 === 3) || (2 > 4) // true

32. http://proglit.com/

33. if / else if(condition) {body} else if(condition){body} else {body} while while(condition) {body}

34. if (x === 3) { foo(); } else { bar(); }

35. var i = 0; while (i < 5) { foo(); i = i + 1; }

36. var foo = function() { return bar; }; foo(); // error var bar = 3; foo(); // OK

37. var foo = function() { bar = 6; return bar; var bar; }; foo(); // 6

38. nested functions var foo = function(a) { var bar = function(b) { returnb + 3; }; returnbar(a); }; foo(5); // 8

39. Function A B C Function A D B C Function E C B D A

40. var foo = function(a) { var bar = function(a) { returna + 3; }; returnbar(a); }; foo(5); // 8

41. var foo = function() { vara = 3; var bar = function(b) { returna + b; }; a = 5; returnbar(6); }; foo(); // 11

42. http://proglit.com/

43. closure var foo = function(a) { var b = 4; return function(c) { returna + b + c; }; }; varbar = foo(2); var ack = foo(3); bar(6); // 12 ack(6); // 13

44. closure var foo = function(a) { return function() { a = a + 2; returna; }; }; varbar = foo(2); var ack = foo(3); bar(); // 4 bar(); // 6 ack(); // 5

45. objects {properties} object[string]

46. var foo = {}; var bar = {“bill”: 1 + 1, “diana”: 11}; var ack = bar[“bill”]; // 2 bar[“bill”] = 3; foo[“ned”] = 8; ack = foo[“ted”]; // undefined

47. var foo = {}; var bar = {bill: 1 + 1, diana: 11}; var ack = bar.bill; // 2 bar.bill = 3; foo.ned = 8; ack = foo.ted; // undefined

48. methods var foo = {}; foo.bar = function() { this.ack = 3; }; foo.bar();

49. var foo = {}; foo.bar = function(x) { x.ack = 3; }; foo.bar(foo);

50. var foo = {}; foo.bar = function() { this = 3; //error }; foo.bar();