public override IExpr Patch(Patch substitutions)
{
XSlice result;
if (substitutions.TryGetValue(this, out result))
{
return(result);
}
var inputsPatched = Inputs.Patch(substitutions);
if (inputsPatched != Inputs)
{
XSlice patched;
if (IsSingleton)
{
patched = new XSlice((Scalar <int>)inputsPatched[0]);
}
else
{
patched = new XSlice((Scalar <int>)inputsPatched[0], (Scalar <int>)inputsPatched[1], (Scalar <int>)inputsPatched[2]);
}
substitutions.Add(this, patched);
return(patched);
}
else
{
return(this);
}
}
public static IReadOnlyList <XSlice> Patch(Patch substitutions, IReadOnlyList <XSlice> slices)
{
var ok = true;
var result = new XSlice[slices.Count];
for (int i = 0; i < result.Length; i++)
{
var slice = slices[i];
result[i] = new XSlice(
(Scalar <int>)slice.Start.Patch(substitutions),
(Scalar <int>)slice.Stop.Patch(substitutions),
(Scalar <int>)slice.Step.Patch(substitutions)
);
if (result[i].Start != slice.Start ||
result[i].Stop != slice.Stop ||
result[i].Step != slice.Step)
{
ok = false;
}
}
if (ok)
{
return(slices);
}
return(result);
}
public static XSlice Step(int step)
{
if (step < 0)
{
return(XSlice.Create(-1, int.MinValue, step));
}
return(XSlice.Create(0, int.MaxValue, step));
}
public static XSlice From(Scalar <int> start, int step = 1)
{
if (step < 0)
{
return(XSlice.Create(start, int.MinValue, step));
}
else
{
return(XSlice.Create(start, int.MaxValue, step));
}
}
public static XSlice Until(Scalar <int> stop, int step = 1)
{
if (step < 0)
{
return(XSlice.Create(-1, stop, step));
}
else
{
return(XSlice.Create(0, stop, step));
}
}
//public static readonly Slice NewAxis = Range(0, 0, int.MaxValue);
public static XSlice Range(Scalar <int> start, Scalar <int> stop, int step = 1)
{
if (stop == null)
{
return(From(start, step));
}
if (start == null)
{
return(Until(stop, step));
}
return(XSlice.Create(start, stop, step));
}
public static XSlice Only(Scalar <int> i) => XSlice.Create(i, i + 1, 0);