You gotta love that name: AdaGOOP.
AdaGOOP 2005 is an Ada 2005 automatic parser generator built on top of the SCATC versions of aflex and ayacc. As SableCC does, AdaGOOP automatically generates code to build a parse tree, and a traversal of the parse tree using the visitor pattern.
From looking at the examples on the website, it seems to be fairly “easy” to use, though I must admit there are some parts of the code that I simply cannot decipher. I need to upgrade my Ada-foo.
This little Ada gem came to my attention via the Ada sub-reddit.