New in JavaScript 1.8 - Archive of obsolete content
when using the javascript shell, javascript xpcom components, or xul <script> elements, the latest js version (js1.8 in mozilla 1.9) is used automatically (bug 381031, bug 385159).

JS_ThrowStopIteration
this article covers features introduced in spidermonkey js1.8 throw a stopiteration exception.

Deprecated and obsolete features - JavaScript
js1.7/js1.8 array comprehension and js1.7/js1.8 generator comprehension are deprecated.