public void CastToStrongTypeUnchanged()
{
object o1 = 25;
object o2 = 75;
ObjectPair pair = new ObjectPair(o1, o2);
Reflection.CastToStrongType(pair);
o1 = pair.First;
o2 = pair.Second;
Assert.IsTrue(o1 is Int32, "(1) o1 type");
Assert.AreEqual(o1, 25, "(1) o1 value");
Assert.IsTrue(o2 is Int32, "(1) o2 type");
Assert.AreEqual(o2, 75, "(1) o2 value");
o1 = "25";
o2 = "75";
pair = new ObjectPair(o1, o2);
Reflection.CastToStrongType(pair);
o1 = pair.First;
o2 = pair.Second;
Assert.IsTrue(o1 is String, "(2) o1 type");
Assert.AreEqual(o1, "25", "(2) o1 value");
Assert.IsTrue(o2 is String, "(2) o2 type");
Assert.AreEqual(o2, "75", "(2) o2 value");
}
public void CastToStrongTypeChanged()
{
object o1 = "25";
object o2 = 75;
ObjectPair pair = new ObjectPair(o1, o2);
Reflection.CastToStrongType(pair);
o1 = pair.First;
o2 = pair.Second;
Assert.IsTrue(o1 is Int32, "(1) o1 type");
Assert.AreEqual(o1, 25, "(1) o1 value");
Assert.IsTrue(o2 is Int32, "(1) o2 type");
Assert.AreEqual(o2, 75, "(1) o2 value");
o1 = Math.PI;
o2 = "-6.55";
pair = new ObjectPair(o1, o2);
Reflection.CastToStrongType(pair);
o1 = pair.First;
o2 = pair.Second;
Assert.IsTrue(o1 is Double, "(2) o1 type");
Assert.AreEqual(o1, Math.PI, "(2) o1 value");
Assert.IsTrue(o2 is Double, "(2) o2 type");
Assert.AreEqual(o2, -6.55d, "(2) o2 value");
}
/// <summary>
/// Converts either object1 to the type of object2, or the contrary, based on the object having
/// the weakest type, i.e. System.String. If none of the objects are System.String
/// object2 will be casted to object1.
/// </summary>
/// <param name="pair">A reference to the pair of objects to cast.</param>
public static void CastToStrongType(ObjectPair pair)
{
if ((pair.First.GetType().GetInterface("System.IConvertible", false) != null) &&
(pair.Second.GetType().GetInterface("System.IConvertible", false) != null))
{
// if they are both convertible, convert to the strongest type (non string)
// or arbitrary cast the second to the first
if (pair.First is System.String)
{
pair.First = CastValue(pair.First, pair.Second.GetType());
}
else
{
pair.Second = CastValue(pair.Second, pair.First.GetType());
}
}
}
/// <summary>
/// Checks if the current Atom matches with another one, i.e. if they are of same type,
/// contain the same number of predicates, and if their Individual predicates are equal.
/// </summary>
/// <description>
/// This functions takes care of casting as it always tries to cast to the strongest type
/// of two compared individuals. Since predicates can come from weakly-typed rule files
/// (Strings) and other predicates can be generated by the user, this function tries to
/// convert from String to the type of the other predicate (as String is considered not
/// strongly typed).
/// </description>
/// <param name="atom">The other atom to determine the matching.</param>
/// <returns>True if the two atoms match.</returns>
public bool Matches(Atom atom)
{
if (!BasicMatches(atom)) return false;
for(int i=0; i<predicates.Length; i++) {
if ((predicates[i] is Individual) &&
(atom.predicates[i] is Function) &&
(!((Function)atom.predicates[i]).Evaluate((Individual)predicates[i])))
return false;
else if ((predicates[i] is Function) &&
(atom.predicates[i] is Individual) &&
(!((Function)predicates[i]).Evaluate((Individual)atom.predicates[i])))
return false;
else if ((predicates[i] is Function) &&
(atom.predicates[i] is Function) &&
(!(predicates[i].Equals(atom.predicates[i]))))
return false;
else if ((predicates[i] is Individual) && (atom.predicates[i] is Individual)) {
// we have two individuals
if ((predicates[i].Value.GetType() == atom.predicates[i].Value.GetType())
&& (!predicates[i].Equals(atom.predicates[i]))) {
// the two individuals are of same types: direct compare
return false;
}
else {
// the two individuals are of different types
ObjectPair pair = new ObjectPair(predicates[i].Value, atom.predicates[i].Value);
Reflection.CastToStrongType(pair);
if (!pair.First.Equals(pair.Second)) return false;
}
}
}
return true;
}
