JavaScript. !

. alert('Hello, world!') Hello, world!. . (;). Hello World :

alert('Hello'); alert('World');

:

alert('Hello');
alert('World');

. :

alert('Hello')
alert('World')

JavaScript (). ( [Automatic semicolon insertion]).

. . . :

alert(3+
1
+2);

6 JavaScript . + (incomplete expression) . . javaScript JavaScript . ( ). :

[1, 2].foreach(alert)

[] forEach . 1 2. (alert) :

alert("There will be an error")
[1 ,2].forEach(alert)

. :

alert("All fine now");
[1 ,2].forEach(alert)

All fine now 1 2. ( ) JavaScript [] . . :

alert("There will be an error")[1, 2].forEach(alert)

. . . JavaScript. .

. . . (forward slash) //. . . :

//       

alert('Hello');
alert('World'); //     

** ( /*) ( */) **. :

/*    

  

*/
alert('Hello');
alert('World');

/**/. :

/*    
alert('Hello');
*/
alert('World');

Ctrl+/ . Ctrl+Shift+/ ( ). Cmd Ctrl.

: . /**/ /**/ :

/*
/* */
*/
alert('World');

.

. . . ( ) . .

-- Code structure The JavaScript Language