index method
Returns an iterable of MapEntry
representing the elements in this iterable combined with
the zero-based index where the element was found.
The returned iterable will consist of a sequence of MapEntry
elements. For each entry,
the key will be the index and the value will be the element itself.
Optionally a startIndex
value can be provided. The first element in the resulting
iterable will begin with that value. (Defaults to 0)
A value can be provided for descending
as well. If true, the indices in the returned
iterable will count down from the starting index. (Defaults to false)
Implementation
Iterable<MapEntry<int, T>> index(
[int startIndex = 0, bool descending = false]) sync* {
var index = startIndex;
for (var o in this) {
yield MapEntry(index, o);
index += descending ? -1 : 1;
}
}