public void ParseAndExpression()
{
IExpression expression = this.ParseExpression("a===1 && b===1");
Assert.IsNotNull(expression);
Assert.IsInstanceOfType(expression, typeof(AndExpression));
AndExpression andexpr = (AndExpression)expression;
Assert.IsInstanceOfType(andexpr.LeftExpression, typeof(CompareExpression));
Assert.IsInstanceOfType(andexpr.RightExpression, typeof(CompareExpression));
}