Antlr4Code is a free VS 2013/2015 extension which I quickly wrote so we have a minimum of editing support for ANTLR4 grammars inside Visual Studio.
Right now it is pretty basic stuff, nothing too fancy, but the essential stuff is there:
- syntax highlighting (looks good among all VS themes)
- semantic analysis
- Go To Definition support for lexer and parser rules
- shows errors squiggles for undefined lexer or parser rules