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What is in JavaScript 1.5?

JavaScript 1.5 adheres to ECMA-262, revision 3 (See the JavaScript futures page for a link to the spec.) created by the ECMA Technical Committee TC39. New features include:

  • ECMA 3 Features
    • Runtime errors reported as exceptions.
    • Number formatting (Number.prototype.toFixed and Number.prototype.toExponential)
    • Regular Expression Enhancements.

  • Additional Features (SpiderMonkey and Rhino)
    • Conditional function declaration. (aka Function Expression Statements) [discussion]
    • Multiple catch clauses (aka catchguards.) [discussion]

  • Additional Features (SpiderMonkey only)
    • Getters and Setters. [discussion]
    • const keyword.
    • "Strict" mode with new warning messages. [discussion]

You can browse the check-in logs and bug reports over the last year, as well as the current open bug list.

When will JavaScript 1.5 be released?

JavaScript 1.5 versions of the SpiderMonkey and Rhino implementations are in the Release Candidate stage NOW! Our internal testing indicates that both engines are passing all existing (non-LiveConnect) test cases on Linux, Solaris, and Windows, and Mac platforms. The final release will occur after RC1 has been proven stable.

Where can I get JavaScript 1.5?

The Rhino and Spidermonkey pages have information on how to get a pre-packaged version of the source code. For completely up-to-date source, both of the JavaScript 1.5 engines are available directly from the Mozilla CVS Repository. JavaScript 1.5 is also part of the Mozilla client.

To check out ONLY the JavaScript section of the tree, issue the command cvs co mozilla/js after properly setting up CVS on your machine.

See the JavaScript README for details on how to build the engine.

The JavaScript test suite is available in the mozilla/js/tests subdirectory. Documentation on the test driver is included with the distribution.

How can I contribute to JavaScript 1.5?

Do you embed JavaScript in your own environment? Do you have a series of tests you run against the JavaScript engine in that environment? If so, you can run your tests against the new engine and share your results. You can send them directly to Rob Ginda, or post them to the JS Engine newsgroup for open discussion. Your feedback will go a long way to keeping the JavaScript 1.5 final as bug free as possible.

Do you have a platform we're not running tests on? If so, run the tests on your platform and Submit the results.

Do you have an interest in writing test cases? If so, check out the test library page. It explains the format of the existing test cases, and guidelines for creating new ones. Many test cases can be pulled right from the ECMA spec.

What comes after JavaScript 1.5?

The next version of JavaScript will be the 2.0 release. 2.0 represents a rewrite of both the language specification and engine implementation, with a strong mind on backward compatibility. Expect to see Classes, Types, and other features more commonly seen in static languages, as well as the existing dynamic features of the JavaScript 1.x releases. Design discussion has started on the JS Engine newsgroup, and in the ECMA TC39 meetings. It is our plan to concentrate fully on creating a fully standards compliant JavaScript 2.0 implementation when 1.5 is complete. See Waldemar's proposal for JavaScript 2.0 and the Future directions page for more information on JavaScript 2.0.
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Robert Ginda
Last modified: Tue Mar 21 17:29:13 PST 2000