@dragos , I haven't tried them yet, but I can see the debugging experience improving with the additional `lineNumber`s in question. This is just an example of how GenBCode allows seeing at all times the correspondence:
- AST node being emitted (`Literal` in this case, `This` in the previous comment)
- bytecode layout

I'm all for adding as many `lineNumber` as necessary to improve the debugging experience (in fact, it's never "wrong" to include additional `lineNumber`s). So far I've included those deemed useful, but this is by no means exhaustive. Feel free to add `lineNumber`s !!!. My suggestion in this regard is: let's not delay this PR just because of those improvements, which can be most easily done on the spot, after this PR has been merged.