Index
Normally, the index is an integer passed to the indexer of an array:
int index = 3;
Person p = people[index]; // The fourth Person in the array.
The Index value type can identify position.
Creating
This index counts from the start:
Index i1 = new(value: 3);
or
Index i2 = 3;
This index counts from the end:
Index i3 = new(value: 7, fromEnd: true);
or
Index i4 = ^7
Range
The Range value type uses Index values to indicate the start and end of its range.
Range r1 = new(start: new Index(3), end: new Index(7));
Range r2 = new(start: 3, end: 7);
Range r3 = 3..7;
Range r4 = Range.StartAt(3); // from index 3 to end
Range r5 = 3..; // same
Range r6 = Range.EndAt(3); // from index 0 to index 3
Range r7 = ..3; // same