private List<Parameter> GetPlaceHolders(Function function, Dictionary<Actual, IValue> parameterValues)
{
List<Parameter> retVal = new List<Parameter>();
foreach (KeyValuePair<Actual, IValue> pair in parameterValues)
{
Actual actual = pair.Key;
PlaceHolder placeHolder = pair.Value as PlaceHolder;
if (placeHolder != null && actual.Parameter.Enclosing == function)
{
retVal.Add(actual.Parameter);
}
}
if (retVal.Count != parameterValues.Count || retVal.Count == 0)
{
retVal = null;
}
return retVal;
}