Structure

SHA256Digest

The output of a Secure Hashing Algorithm 2 (SHA-2) hash with a 256-bit digest.

Declaration

struct SHA256Digest

Topics

Getting the Digest Length

static var byteCount: Int

The number of bytes in the SHA256 digest.

Comparing Digests

static func == (SHA256Digest, SHA256Digest) -> Bool

Determines whether two digests are equal.

static func != (SHA256Digest, SHA256Digest) -> Bool

Determines whether two digests are not equal.

func elementsEqual<OtherSequence>(OtherSequence) -> Bool

Returns a Boolean value indicating whether this sequence and another sequence contain the same elements in the same order.

func elementsEqual<OtherSequence>(OtherSequence, by: (UInt8, OtherSequence.Element) -> Bool) -> Bool

Returns a Boolean value indicating whether this sequence and another sequence contain equivalent elements in the same order, using the given predicate as the equivalence test.

func starts<PossiblePrefix>(with: PossiblePrefix) -> Bool

Returns a Boolean value indicating whether the initial elements of the sequence are the same as the elements in another sequence.

func starts<PossiblePrefix>(with: PossiblePrefix, by: (UInt8, PossiblePrefix.Element) -> Bool) -> Bool

Returns a Boolean value indicating whether the initial elements of the sequence are equivalent to the elements in another sequence, using the given predicate as the equivalence test.

func lexicographicallyPrecedes<OtherSequence>(OtherSequence) -> Bool

Returns a Boolean value indicating whether the sequence precedes another sequence in a lexicographical (dictionary) ordering, using the less-than operator (<) to compare elements.

func lexicographicallyPrecedes<OtherSequence>(OtherSequence, by: (UInt8, UInt8) -> Bool) -> Bool

Returns a Boolean value indicating whether the sequence precedes another sequence in a lexicographical (dictionary) ordering, using the given predicate to compare elements.

Iterating Over the Bytes of a Digest

func makeIterator() -> Array<UInt8>.Iterator

Generates an iterator over the bytes of the digest.

typealias SHA256Digest.Iterator

A type for the iterator over the digest.

typealias SHA256Digest.Element

A type for the elements of the digest.

func forEach((UInt8) -> Void)

Calls the given closure on each element in the sequence in the same order as a for-in loop.

func enumerated() -> EnumeratedSequence<SHA256Digest>

Returns a sequence of pairs (n, x), where n represents a consecutive integer starting at zero and x represents an element of the sequence.

var underestimatedCount: Int

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

Finding Bytes

func contains(UInt8) -> Bool

Returns a Boolean value indicating whether the sequence contains the given element.

func contains(where: (UInt8) -> Bool) -> Bool

Returns a Boolean value indicating whether the sequence contains an element that satisfies the given predicate.

func allSatisfy((UInt8) -> Bool) -> Bool

Returns a Boolean value indicating whether every element of a sequence satisfies a given predicate.

func first(where: (UInt8) -> Bool) -> UInt8?

Returns the first element of the sequence that satisfies the given predicate.

func min() -> UInt8?

Returns the minimum element in the sequence.

func min(by: (UInt8, UInt8) -> Bool) -> UInt8?

Returns the minimum element in the sequence, using the given predicate as the comparison between elements.

func max() -> UInt8?

Returns the maximum element in the sequence.

func max(by: (UInt8, UInt8) -> Bool) -> UInt8?

Returns the maximum element in the sequence, using the given predicate as the comparison between elements.

Selecting Bytes

func filter((UInt8) -> Bool) -> [UInt8]

Returns an array containing, in order, the elements of the sequence that satisfy the given predicate.

func prefix(Int) -> PrefixSequence<SHA256Digest>

Returns a sequence, up to the specified maximum length, containing the initial elements of the sequence.

func prefix(while: (UInt8) -> Bool) -> [UInt8]

Returns a sequence containing the initial, consecutive elements that satisfy the given predicate.

func suffix(Int) -> [UInt8]

Returns a subsequence, up to the given maximum length, containing the final elements of the sequence.

Transforming a Digest

func map<T>((UInt8) -> T) -> [T]

Returns an array containing the results of mapping the given closure over the sequence’s elements.

func flatMap<SegmentOfResult>((UInt8) -> SegmentOfResult) -> [SegmentOfResult.Element]

Returns an array containing the concatenated results of calling the given transformation with each element of this sequence.

func flatMap<ElementOfResult>((UInt8) -> ElementOfResult?) -> [ElementOfResult]

Generates an array containing the non-nil results of calling the given transformation with each byte of the digest.

Deprecated
func compactMap<ElementOfResult>((UInt8) -> ElementOfResult?) -> [ElementOfResult]

Returns an array containing the non-nil results of calling the given transformation with each element of this sequence.

func reduce<Result>(Result, (Result, UInt8) -> Result) -> Result

Returns the result of combining the elements of the sequence using the given closure.

func reduce<Result>(into: Result, (inout Result, UInt8) -> ()) -> Result

Returns the result of combining the elements of the sequence using the given closure.

var lazy: LazySequence<SHA256Digest>

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

Reordering Bytes

func sorted() -> [UInt8]

Returns the elements of the sequence, sorted.

func sorted(by: (UInt8, UInt8) -> Bool) -> [UInt8]

Returns the elements of the sequence, sorted using the given predicate as the comparison between elements.

func reversed() -> [UInt8]

Returns an array containing the elements of this sequence in reverse order.

func shuffled() -> [UInt8]

Returns the elements of the sequence, shuffled.

func shuffled<T>(using: inout T) -> [UInt8]

Returns the elements of the sequence, shuffled using the given generator as a source for randomness.

Excluding Bytes

func dropFirst(Int) -> DropFirstSequence<SHA256Digest>

Returns a sequence containing all but the given number of initial elements.

func dropLast(Int) -> [UInt8]

Returns a sequence containing all but the given number of final elements.

func drop(while: (UInt8) -> Bool) -> DropWhileSequence<SHA256Digest>

Returns a sequence by skipping the initial, consecutive elements that satisfy the given predicate.

Splitting a Digest

func split(separator: UInt8, maxSplits: Int, omittingEmptySubsequences: Bool) -> [ArraySlice<UInt8>]

Returns the longest possible subsequences of the sequence, in order, around elements equal to the given element.

func split(maxSplits: Int, omittingEmptySubsequences: Bool, whereSeparator: (UInt8) -> Bool) -> [ArraySlice<UInt8>]

Returns the longest possible subsequences of the sequence, in order, that don’t contain elements satisfying the given predicate. Elements that are used to split the sequence are not returned as part of any subsequence.

Accessing Underlying Storage

func withContiguousStorageIfAvailable<R>((UnsafeBufferPointer<UInt8>) -> R) -> R?

Call body(p), where p is a pointer to the collection’s contiguous storage. If no such storage exists, it is first created. If the collection does not support an internal representation in a form of contiguous storage, body is not called and nil is returned.

func withUnsafeBytes<R>((UnsafeRawBufferPointer) -> R) -> R

Invokes the given closure with a buffer pointer covering the raw bytes of the digest.

Describing a Digest

var description: String

A human readable description of the digest.

Hashing a Digest

func hash(into: inout Hasher)

Hashes the essential components of the digest by feeding them into the given hash function.

var hashValue: Int

The hash value of the digest.

See Also

Specifying the Output Type

typealias SHA256.Digest

The digest type for a SHA256 hash function.