public void ParseTrueAsConstant()
{
IExpression expression = this.ParseExpression("true");
Assert.IsNotNull(expression);
Assert.IsInstanceOfType(expression, typeof(ConstantExpression));
ConstantExpression consexpr = (ConstantExpression)expression;
Assert.IsInstanceOfType(consexpr.Value, typeof(bool));
Assert.IsTrue((bool)consexpr.Value);
}