Essentials of Javascript - Cultural View

JavaScript 13
1.5 November
2000
1.6 November
2005
ECMA-262 3 rd edition 6.0 1.0 5.5 (JScript
5.5),
1.5 + Array extras + Array and String generics +
1.7 October 2006 1.6 + Pythonic generators + Iterators + let 2.0
1.8 June 2008 1.7 + Generator expressions + Expression closures 3.0
1.8.1 1.8 + Native JSON support + Minor Updates 3.5
1.8.2 1.8.1 + Minor updates 3.6
1.9 1.8.1 + ECMAScript 5 Compliance 4
[70]
E4X
Related languages and features
6 (JScript 5.6),
7 (JScript 5.7),
8 (JScript 5.8)
Since the acceptance of JavaScript as a popular language, several languages and features have developed from it.
Objective-J is a strict superset of JavaScript that adds traditional inheritance and Smalltalk/Objective-C style
dynamic dispatch and optional pseudo-static typing to pure JavaScript.
TIScript is a superset of JavaScript that adds classes, namespaces and lambda expressions.
JSON, or JavaScript Object Notation, is a general-purpose data interchange format that is defined as a subset of
JavaScript.
Mozilla browsers currently support LiveConnect, a feature that allows JavaScript and Java to intercommunicate on
the web. However, Mozilla-specific support for LiveConnect is scheduled to be phased out in the future in favor of
passing on the LiveConnect handling via NPAPI to the Java 1.6+ plug-in (not yet supported on the Mac as of March
2010). [71]
JavaScript and Java
A common misconception is that JavaScript is similar or closely related to Java. It is true that both have a C-like
syntax, the C language being their most immediate common ancestor language. They are both object-oriented,
typically sandboxed (when used inside a browser), and are widely used in client-side Web applications. In addition,
JavaScript was designed with Java's syntax and standard library in mind. In particular, all Java keywords are
reserved in JavaScript, JavaScript's standard library follows Java's naming conventions, and JavaScript's Math and
Date objects are based on classes from Java 1.0. [17]
But the similarities end there. Java has static typing; JavaScript's typing is dynamic (meaning a variable can hold an
object of any type and cannot be restricted). Java is loaded from compiled bytecode; JavaScript is loaded as
human-readable source code. Java's objects are class-based; JavaScript's are prototype-based. JavaScript also has
many functional features based on the Self language.
1.5
6.0,
7.0,
8.0,
9.0,
10.0
3.0,
3.1,
3.2,
4.0
1.0