Antlr.Runtime.BufferedTokenStream.Consume C# (CSharp) Method

        public virtual void Consume()
        {
            if (_p == -1)
                Setup();
            _p++;
            Sync(_p);
        }

        public void TestLookback()
        {
            Grammar g = new Grammar(
                "lexer grammar t;\n" +
                "ID : 'a'..'z'+;\n" +
                "INT : '0'..'9'+;\n" +
                "SEMI : ';';\n" +
                "ASSIGN : '=';\n" +
                "PLUS : '+';\n" +
                "MULT : '*';\n" +
                "WS : ' '+;\n");
            // Tokens: 012345678901234567
            // Input:  x = 3 * 0 + 2 * 0;
            ICharStream input = new ANTLRStringStream("x = 3 * 0 + 2 * 0;");
            Interpreter lexEngine = new Interpreter(g, input);
            BufferedTokenStream tokens = new BufferedTokenStream(lexEngine);

            tokens.Consume(); // get x into buffer
            IToken t = tokens.LT(-1);
            Assert.AreEqual("x", t.Text);

            tokens.Consume();
            tokens.Consume(); // consume '='
            t = tokens.LT(-3);
            Assert.AreEqual("x", t.Text);
            t = tokens.LT(-2);
            Assert.AreEqual(" ", t.Text);
            t = tokens.LT(-1);
            Assert.AreEqual("=", t.Text);
        }