private void checkAttribution() throws Exception {
		if(iterator < tokenList.size() && tokenList.get(iterator++).getType() != TokenType.ATTR) {
			// missing attribution symbol
			throw new Exception("Syntax Error at line " + tokenList.get(iterator-1).getLine() + 
					": Expected = and got \"" + tokenList.get(iterator-1).getKey() + "\" instead");
		}
		
		checkArithmeticExpression();
		
		if(iterator < tokenList.size() && tokenList.get(iterator++).getType() != TokenType.SEMICOLLON) {
			// missing semicollon
			throw new Exception("Syntax Error at line " + tokenList.get(iterator-1).getLine() + 
					": Expected ; and got \"" + tokenList.get(iterator-1).getKey() + "\" instead");
		}
	}