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Until recently the use of @Grab to pull in source file dependencies was not recognized by groovy eclipse, resulting in a compilation error for the type that would have been located by following the Grab. Now they are being recognized. The @Grab referenced dependencies are added to the classpath used under the covers to build the project. Content assist is also possible for references to @Grab'd types. Grabbed dependencies are not currently reflected anywhere in the eclipse project metadata (ie. they are not seen in the classpath Eclipse manages for the project) - this may change in a future version of Groovy Eclipse.
When using @Grab, the Grab'd types are available through content assist and unknown references are underlined. In the following screenshot, you can see that the Joda-Time API can be verified and used within the editor even though its jars are only available through @Grab:
Launching Groovy scripts
Launching groovy scripts is now easier and more robust. We have addressed some key bugs in this area: GRECLIPSE-555, GRECLIPSE-560, GRECLIPSE-478.
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