private void checkMessage() throws Exception {
		if(iterator < tokenList.size() && tokenList.get(iterator++).getType() != TokenType.ID &&
				tokenList.get(iterator-1).getType() != TokenType.STRING) {
			// missing print arguments
			throw new Exception("Syntax Error at line " + tokenList.get(iterator-1).getLine() + 
					": Expected print argument and got \"" + tokenList.get(iterator-1).getKey() + "\" instead");
		}
		
		if(iterator < tokenList.size() && tokenList.get(iterator).getType() == TokenType.COMMA) {
			iterator++;
			checkMessage();
		}
	}