[wbhart]

No, this is not stretching the definition at all. There is no way to recreate the source of the parser generator from the automatically generated parser and grammar files. And in fact it would be entirely non-trivial to recreate it.

The parser also likely contains large tables of values autogenerated by the parser generator (though I didn't check this). There is no way the average developer could modify the parser to suit their needs. This would be even more difficult than disassembling a binary and altering the assembly language.

In a way I am glad this happened. After a months long ordeal some years ago involving strongly worded letters with threatening legal language due to an accidental violation of the GPL (which I simply don't use for new projects any more) I now have an uncontentious example that I can point people to which shows that even developers with the best of intentions make "serious" accidental mistakes!