One of the rationales behind Jangaroo is to make the good parts of static typing, such as getting reliable and useful IDE support, available for the dynamic language JavaScript. This is described in more detail in the Jangaroo tools wiki.
Recent versions of the IDE IntelliJ IDEA Ultimate Edition
have built-in support for ActionScript and JavaScript development. Jangaroo provides an IDEA
plugin called Jangaroo 0.9, which bundles the functionality
of two older plugins (Jangaroo Language for compiling
ActionScript as described at
https://github.com/CoreMedia/jangaroo-tools/wiki/Developing-Jangaroo-Applications-with-IntelliJ-IDEA
and Jangaroo EXML for compiling .exml
files as described at
https://github.com/CoreMedia/jangaroo-tools/wiki/Developing-Ext-AS-Applications-with-IntelliJ-IDEA).
The older plugins should not be activated jointly with the current unified
Jangaroo 0.9 plugin. They are still available for projects
working with older Jangaroo versions, but will eventually be deleted.