There is still a lot of mel code around.  In order to edit it within Eclipse another editor type can be used.  This is provided by the Colorer Plugin

1. Download the Maya mel data file (see download link above).

2. Use the following link to install the Colorer plugin in the "Install new software" page:
Eclipse's Update Manager URL: https://colorer.sf.net/eclipsecolorer/

3. find the Eclipse plugin directory and navigate to:
.../plugins/net.sf.colorer_0.9.9/colorer/hrc/

4. Unzip the eclipseColorer_mel.zip into this folder which will replace 2 files there. 

5. Relaunch Eclipse. 

You can assign .mel file extensions to always open using the Colorer plugin as default.  You can change color schemes and make your own.

Those that find this useful and want to develop the mel.hrc file further (it's a language parser) and want to share what you've done, contact me to update these files. 

There are over 250 other syntax highlighting options with this plugin including RIB.