An enumeration of the elements of a sequence or collection.

@frozen struct EnumeratedSequence<Base> where Base : Sequence


EnumeratedSequence is a sequence of pairs (n, x), where ns are consecutive Int values starting at zero, and xs are the elements of a base sequence.

To create an instance of EnumeratedSequence, call enumerated() on a sequence or collection. The following example enumerates the elements of an array.

var s = ["foo", "bar"].enumerated()
for (n, x) in s {
    print("\(n): \(x)")
// Prints "0: foo"
// Prints "1: bar"


Instance Properties

  • var lazy: LazySequence<Self>

    A sequence containing the same elements as this sequence, but on which some operations, such as map and filter, are implemented lazily.

  • var underestimatedCount: Int

    A value less than or equal to the number of elements in the sequence, calculated nondestructively.

Instance Methods


Conforms To

Removed Members