Replace parser with ANTLR

https://github.com/antlr/antlr4

grammar RGBDS;

// Lexer rules
NUMBER: [0-9]+;
IDENTIFIER: [a-zA-Z_][a-zA-Z0-9_]*;
COMMENT: ';' ~[\r\n]* -> skip;
WHITESPACE: [ \t\r\n]+ -> skip;

// Assembly instructions and directives
opcode: IDENTIFIER;

// Labels
label: IDENTIFIER ':';

// Instructions
instruction: opcode (NUMBER | IDENTIFIER)?;

// Main entry point
statement: label? instruction?;

// Parsing multiple statements
program: statement+;

using Antlr4.Runtime;
using System;

class Program
{
    static void Main(string[] args)
    {
        string input = @"
        label1: nop
        ld a, 5
        ";

        AntlrInputStream inputStream = new AntlrInputStream(input);
        RGBDSLexer lexer = new RGBDSLexer(inputStream);
        CommonTokenStream tokenStream = new CommonTokenStream(lexer);
        RGBDSParser parser = new RGBDSParser(tokenStream);

        RGBDSParser.ProgramContext context = parser.program();
        Console.WriteLine(context.ToStringTree(parser));
    }
}

archanox / RGBDS2CIL

Replace parser with ANTLR #159