assertEquals(lexSource.lookAheadElement(3).source, "gh");
assertEquals(lexSource.lookAheadElement(4).type, DeeTokens.EOF);
lexSource.consumeInput();
assertEquals(lexSource.lastLexElement().source, "ab");
assertEquals(lexSource.lookAheadElement(0).source, "cd");
assertEquals(lexSource.lookAheadElement(1).source, "ef");
assertEquals(lexSource.lookAheadElement(1).getFullRangeStartPos(), 4);
assertEquals(lexSource.lookAheadElement(1).getStartPos(), 6);
assertEquals(lexSource.lookAheadElement(2).source, "gh");
assertEquals(lexSource.lookAheadElement(3).type, DeeTokens.EOF);