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This page contains instructions for setting up the Eclipse Integrated-Development-Environment (IDE), and to configure it's XML editing features so that they provide some level of support for authoring DFDL schemas. In theory, based on this, if you have some other favorite XML-Schema-Aware editing environment, you could figure out how to enable it to provide you similar DFDL schema authoring assistance.
Installing Eclipse XML Features
The XML settings all assume you have installed Eclipse's XML support. Given an Eclipse update site for your version of Eclipse, the "Eclipse XML Editors and Tools" software is what you need, and what this page is referring to for XML settings.
Eclipse XML Settings
(Caveat: The menu locations often vary from one Eclipse release to the next.)
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