private static Filtering <ZipPair <int, TSourceItem> > getFiltering(
Zipping <int, TSourceItem> zipping, Expression <Func <ZipPair <int, TSourceItem>, bool> > zipPairNotPredicateExpression,
Computing <int> countComputing,
int capacity)
{
return(zipping.Filtering(zp => zp.LeftItem >= zipping.Filtering(zipPairNotPredicateExpression, capacity).Selecting(zp1 => zp1.LeftItem).Using(ic => ic.Count > 0 ? ic.Minimazing().Value : countComputing.Value).Value, capacity));
}
private static INotifyCollectionChanged getSource(
INotifyCollectionChanged source,
int startIndex,
int count)
{
Zipping <int, TSourceItem> zipping = new Computing <int>(() => ((IList)source).Count).SequenceComputing()
.Zipping <int, TSourceItem>(source);
return(zipping.Filtering(zp => zp.LeftItem >= startIndex && zp.LeftItem < startIndex + count, count));
}
private static INotifyCollectionChanged getSource(
INotifyCollectionChanged source,
IReadScalar <int> startIndexScalar,
IReadScalar <int> countScalar,
int capacity)
{
Zipping <int, TSourceItem> zipping = new Computing <int>(() => ((IList)source).Count).SequenceComputing()
.Zipping <int, TSourceItem>(source);
return(zipping.Filtering(zp => zp.LeftItem >= startIndexScalar.Value && zp.LeftItem < startIndexScalar.Value + countScalar.Value, capacity));
}
private static INotifyCollectionChanged getSource(
IReadScalar <INotifyCollectionChanged> sourceScalar,
int startIndex,
int count)
{
Zipping <int, TSourceItem> zipping =
new Computing <int>(() => sourceScalar.Value != null ? ((IList)sourceScalar.Value).Count : 0)
.SequenceComputing()
.Zipping <int, TSourceItem>(sourceScalar);
return(zipping.Filtering(zp => zp.LeftItem >= startIndex && zp.LeftItem < startIndex + count, count));
}
private static INotifyCollectionChanged getSource(
INotifyCollectionChanged source,
Expression <Func <TSourceItem, int, bool> > predicateExpression,
int capacity)
{
Expression <Func <ZipPair <int, TSourceItem>, bool> > zipPairNotPredicateExpression = getZipPairNotPredicateExpression(predicateExpression);
Computing <int> countComputing = Expr.Is(() => source != null ? ((IList)source).Count : 0).Computing();
Zipping <int, TSourceItem> zipping = countComputing.SequenceComputing()
.Zipping <int, TSourceItem>(source);
return(getFiltering(zipping, zipPairNotPredicateExpression, countComputing, capacity));
}
private static INotifyCollectionChanged getSource(
IReadScalar <INotifyCollectionChanged> sourceScalar,
Expression <Func <TSourceItem, int, bool> > predicateExpression,
int capacity)
{
Expression <Func <ZipPair <int, TSourceItem>, bool> > zipPairNotPredicateExpression = getZipPairNotPredicateExpression(predicateExpression);
Computing <int> countComputing = Expr.Is(() => sourceScalar.Value != null ? ((IList)sourceScalar.Value).Count : 0).Computing();
Zipping <int, TSourceItem> zipping = countComputing.SequenceComputing()
.Zipping <int, TSourceItem>(sourceScalar);
return(getFiltering(zipping, zipPairNotPredicateExpression, countComputing, capacity));
//return () => (INotifyCollectionChanged)Expr.Is(() => (INotifyCollectionChanged)getSource.Computing().Using(sc =>
// Expr.Is(() => ((IList) sc.Value).Count).SequenceComputing()
// .Zipping<int, TSourceItem>(() => sc.Value)).Value).Computing().Using(zipping => zipping.Value.Filtering<ZipPair<int, TSourceItem>>(zp => zp.ItemLeft < zipping.Value.Filtering(zipPairNotPredicateExpression).Selecting(zp1 => zp1.ItemLeft).Minimazing(() => (((IList)zipping.Value).Count)).Value)).Value;
}
public NullPropagating(
IReadScalar <TValue> source,
Expression <Func <TValue, TResult> > getValueExpression)
{
_source = source;
_getValueExpression = getValueExpression;
MemberExpression getSourceValueExpression = Expression.PropertyOrField(Expression.Constant(source), nameof(IReadScalar <TValue> .Value));
_computing = new Computing <TResult>(
Expression.Lambda <Func <TResult> >(
Expression.Condition(
Expression.NotEqual(
getSourceValueExpression,
Expression.Constant(null, typeof(TValue))),
new ReplaceParameterVisitor(
new Dictionary <ParameterExpression, Expression>()
{
{ getValueExpression.Parameters[0], getSourceValueExpression }
}).Visit(getValueExpression.Body),
Expression.Constant(default(TResult), typeof(TResult)))));
}
