public Expression ToSum()
{
if (Deleted)
{
throw new NullReferenceException();
}
foreach (Expression eProdComponent in SubExpressions)
{
if (eProdComponent is SumExpression)
{
SumExpression eSum = (SumExpression)eProdComponent;
SumExpression eNew = MemoryAllocationUnit.GetInstance().NewSumExpression();
foreach (Expression eSumComponent in eSum.SubExpressions)
{
ProductExpression eProd = MemoryAllocationUnit.GetInstance().NewProductExpression();
eProd.AddSubExpression(eSumComponent);
foreach (Expression eOtherProdComponent in SubExpressions)
{
if (eOtherProdComponent != eSum)
{
eProd.AddSubExpression(eOtherProdComponent);
}
}
eNew.AddSubExpression(eProd);
}
return(eNew);
}
}
return(this);
}
static void TestExpressionsI()
{
Expression eOne = MemoryAllocationUnit.GetInstance().NewValueExpression(1);
Expression eTwo = MemoryAllocationUnit.GetInstance().NewValueExpression(2);
Expression eThree = MemoryAllocationUnit.GetInstance().NewValueExpression(3);
SumExpression eSum12 = MemoryAllocationUnit.GetInstance().NewSumExpression();
eSum12.AddSubExpression(eOne);
eSum12.AddSubExpression(eTwo);
SumExpression eSum23 = MemoryAllocationUnit.GetInstance().NewSumExpression();
eSum23.AddSubExpression(eTwo);
eSum23.AddSubExpression(eThree);
ProductExpression eProd = MemoryAllocationUnit.GetInstance().NewProductExpression();
eProd.AddSubExpression(eSum12);
eProd.AddSubExpression(eSum23);
Debug.WriteLine(eProd);
Debug.WriteLine(eProd.Evaluate());
Expression eConverted = eProd.ConvertProductOfSumToSumOfProducts();
Debug.WriteLine(eConverted);
Debug.WriteLine(eConverted.Evaluate());
List <Expression> lRoot = new List <Expression>();
lRoot.Add(eConverted);
MemoryAllocationUnit.GetInstance().GarbageCollection(lRoot);
int cCollectedObjects = MemoryAllocationUnit.GetInstance().CollectedCount;
//should be 5 with the example above
int iResult = eConverted.Evaluate();
}
static void TestExpressionsII(bool bPreserveProduct)
{
Expression eOne = MemoryAllocationUnit.GetInstance().NewValueExpression(1);
Expression eTwo = MemoryAllocationUnit.GetInstance().NewValueExpression(2);
Expression eThree = MemoryAllocationUnit.GetInstance().NewValueExpression(3);
SumExpression eSum12 = MemoryAllocationUnit.GetInstance().NewSumExpression();
eSum12.AddSubExpression(eOne);
eSum12.AddSubExpression(eTwo);
SumExpression eSum23 = MemoryAllocationUnit.GetInstance().NewSumExpression();
eSum23.AddSubExpression(eTwo);
eSum23.AddSubExpression(eThree);
ProductExpression eProd23 = MemoryAllocationUnit.GetInstance().NewProductExpression();
eProd23.AddSubExpression(eTwo);
eProd23.AddSubExpression(eThree);
ProductExpression eProd = MemoryAllocationUnit.GetInstance().NewProductExpression();
eProd.AddSubExpression(eSum12);
eProd.AddSubExpression(eSum23);
Debug.WriteLine(eProd);
SumExpression eSum = MemoryAllocationUnit.GetInstance().NewSumExpression();
eSum.AddSubExpression(eProd23);
eSum.AddSubExpression(eThree);
List <Expression> lRoot = new List <Expression>();
if (bPreserveProduct)
{
lRoot.Add(eProd);
MemoryAllocationUnit.GetInstance().GarbageCollection(lRoot);
int cCollectedObjects = MemoryAllocationUnit.GetInstance().CollectedCount;
//should be 2 with the example above:
//eSum and eProd23 should be removed because they do not appear under eProd
int iResult = eProd.Evaluate();
eSum.Evaluate(); //should generate an exception
}
else
{
lRoot.Add(eSum);
MemoryAllocationUnit.GetInstance().GarbageCollection(lRoot);
int cCollectedObjects = MemoryAllocationUnit.GetInstance().CollectedCount;
//should be 4 with the example above:
//eProd, eSum12, eSum23, eOne do not appear under eSum
int iResult = eSum.Evaluate();
eProd.Evaluate(); //should generate an exception
}
}