intersperse method

Iterable<A> intersperse(A item, { bool beforeFirst = false, bool afterLast = false, })

Creates a new Iterable with the separator interposed between elements.

If beforeFirst is true, the separator is prepended to the iterable (if it has at least one element).

If afterLast is true, the separator is appended to the iterable (if it has at least one element).

Implementation

Iterable<A> intersperse(
  A item, {
  bool beforeFirst = false,
  bool afterLast = false,
}) sync* {
  final iterator = this.iterator;

  if (iterator.moveNext()) {
    if (beforeFirst) {
      yield item;
    }

    yield iterator.current;
    while (iterator.moveNext()) {
      yield item;
      yield iterator.current;
    }

    if (afterLast) {
      yield item;
    }
  }
}