5. This will be worked on a feature branch `dev-new-parser`, so it should not affect `main` until its incorporation.
On Tue, Feb 27, 2024 at 12:32 PM Toshiya Kobayashi < [email protected]> wrote: > Hi, > > The current DRL parser is Antlr3 based and contains lots of hard-coded > logic in generated java codes, so it's hard to maintain. > > for example) > > https://github.com/apache/incubator-kie-drools/blame/main/drools-drl/drools-drl-parser/src/main/java/org/drools/drl/parser/lang/DRL6Parser.java > > The proposal is to develop a new DRL parser based on Antlr4, which has > Visior and Listener support, so the parser would have cleaner separation > between parser syntax and Java code. > > 1. This doesn't target v10.0 release. Fixing all issues keeping backward > compatibility is a large effort. I don't expect that we can complete it > within a month. Even if we can do it more quickly, I don't want to disrupt > the v10.0 release, so the incorporation would be post v10.0. > > 2. The goal of this change is just for code maintainability (e.g. easy to > extend DRL syntax in the future). This is an implementation detail, so > should not impact users. > > 3. Regarding stability, this is something to be discussed further, but > personally I guess we will keep both old and new parsers until we are > confident that the new parser has matured. During the time, we would have > the complexity, but users can switch back to the old parser when there is > an issue with a new parser. > > 4. As a bonus, `antlr4-c3` would help to develop DRL code completion for > LSP (Language Server Protocol), but it's not a direct scope of this > proposal. > > Feel free to share your thoughts. > > Thanks! > Toshiya >
