public void TestExampleTransforms()
{
// These examples are listed in the documentation of FVList.Transform().
// There are more Transform() tests in VListTests() and RWListTests().
VList <int> list = new VList <int>(new int[] { -1, 2, -2, 13, 5, 8, 9 });
VList <int> output;
output = list.Transform((int i, ref int n) =>
{ // Keep every second item
return((i % 2) == 1 ? XfAction.Keep : XfAction.Drop);
});
ExpectList(output, 2, 13, 8);
output = list.Transform((int i, ref int n) =>
{ // Keep odd numbers
return((n % 2) != 0 ? XfAction.Keep : XfAction.Drop);
});
ExpectList(output, -1, 13, 5, 9);
output = list.Transform((int i, ref int n) =>
{ // Keep and square all odd numbers
if ((n % 2) != 0)
{
n *= n;
return(XfAction.Change);
}
else
{
return(XfAction.Drop);
}
});
ExpectList(output, 1, 169, 25, 81);
output = list.Transform((int i, ref int n) =>
{ // Increase each item by its index
n += i;
return(i == 0 ? XfAction.Keep : XfAction.Change);
});
ExpectList(output, -1, 3, 0, 16, 9, 13, 15);
list = new VList <int>(new int[] { 1, 2, 3 });
output = list.Transform(delegate(int i, ref int n) {
return(i >= 0 ? XfAction.Repeat : XfAction.Keep);
});
ExpectList(output, 1, 1, 2, 2, 3, 3);
output = list.Transform(delegate(int i, ref int n) {
if (i >= 0)
{
return(XfAction.Repeat);
}
n *= 10;
return(XfAction.Change);
});
ExpectList(output, 1, 10, 2, 20, 3, 30);
output = list.Transform(delegate(int i, ref int n) {
if (i >= 0)
{
n *= 10;
return(XfAction.Repeat);
}
return(XfAction.Keep);
});
ExpectList(output, 10, 1, 20, 2, 30, 3);
output = list.Transform(delegate(int i, ref int n) {
n *= 10;
if (n > 1000)
{
return(XfAction.Drop);
}
return(XfAction.Repeat);
});
ExpectList(output, 10, 100, 1000, 20, 200, 30, 300);
}
