- Simple text: shows the result of the expression as GHCi would
- HTML/SVG: renders HTML markup and SVG images in a SWT Browser element. In the screenshot there's Blaze HTML and Diagrams SVG
- JSON: display JSON objects and arrays in a tree
We use BuildWrapper and the GHC API to execute the expressions every time the file is saved. The expressions are persistent and hence survive restarting Eclipse.
I don't know when EclipseFP 2.6 will be released, but you can of course get the current code from github.