public override bool VisitStmtPreDefineAbsolute([NotNull] GamaPreprocessorParser.StmtPreDefineAbsoluteContext context)
        {
            var name = context.Symbol().GetText();

            if (Defines.ContainsKey(name))
            {
                return(false);
            }
            Defines.Add(name, context.NonNewlineString().GetText());
            return(true);
        }