Generating files for separated grammar

[blin04]

Hello!
I have a probably very simple question, but for some reason I just can't find a solution to it. I am trying to parse a C++ code for my project (I'm building a transpiler). The grammar for C++ is separated, namely it doesn't have a single .g4 file but it has two of them, CPP14Lexer.g4 and CPP14Parser.g4. How can I generate parser this way? When I used a singe .g4 file, I did it with this command in my command prompt:
antlr4 -Dlanguage=Python3 -visitor GrammarName.g4
Thank you very much for your help!

[mildmojo]

Aha! There's two of us! I also struggled to find this documented anywhere, even in off-site tutorials! After a lot of searching, I started experimenting, and your command should look something like:

antlr4 -Dlanguage=Python3 -visitor GrammarName.g4 LexerName.g4

To build a split grammar with ANTLR, you pass both the lexer and parser grammar files as arguments to antlr4.

When providing split grammar files, ANTLR seems to pass the filenames through to the parser/lexer output files, so it won't tack on Parser anymore. I renamed my grammar files langParser.g4 and langLexer.g4.

[kaby76]

Notes:

• Install this toolkit. It will make your life easier.
• To generate the parser, type antlr4 -Dlanguage=Python3 *.g4.
• grammars-v4/cpp is not "target agnostic". It is not tested for Python3. You'll have to clean up the pureSpecifier rule.