FoundationExtensions

A miscellaneous collection of extensions to Apple's Foundation framework.

AsyncSequence

• collect(upTo:stripTerminator:) gathers items from the sequence into a RangeReplaceableCollection of your choosing, up until either the end of the sequence or the given terminator subsequence is encountered. The terminator can optionally be included in the returned collection.

BidirectionalCollection

• longestPrefix(where:) determines the longest prefix that matches a given condition (optionally performing a transformation on that prefix, as well), using a binary search.

BinaryInteger

• bits returns the individual bits of an integer, in an array. e.g. 19.bits -> [1, 2, 16].
• bitIndices is like bits but returns the indices (as an IndexSet) instead of the values themselves, e.g. 19.bitIndices -> IndexSet([0...1], 4).

Collections of UInt8s (e.g. Array[UInt8], Data, etc)

• asHexString(uppercase:delimiterEvery:delimiter:) formats a Data into hex (as a String), e.g. Data(bytes: "woot", count: 4).asHexString(delimiterEvery: 1) -> "77 6F 6F 74".
  • It also has a shorthand version asHexString for convenience (omitting the parentheses), if you don't need to customise its defaults.

Comparable (e.g. numbers, strings, anything you can put into a range, etc).

• clamp and clamped to conform a value into a given range (supporting all finite range types), e.g. 5.clamped(..<0) -> -1.
  • Note: up-to-but-not-including ranges (..<) are only supported on types that are also Strideable.

Data

• asString(encoding:) is a more ergonomic version of String(data:encoding:).
  • It has a shorthand version asString which assumes UTF-8.

Date

• timeAgo returns a human-readable, localised description of how long ago a given Date was, e.g. "2 hours ago".

Float & Double

• intMax is the upper bound of the range of integer values that can be accurately represented in the respective floating-point type.

IteratorProtocol

• async to return an async version of a sync iterator.
• typeErased property to convert the iterator to AnyIterator, as a convenience for cases such as optional chaining.

Locale

• POSIX is a simple constant for the POSIX locale, as a convenience so you can write Locale.POSIX instead of Locale(identifier: "en_US_POSIX").

Optional

• orNilString returns a String describing the contents or the string literal "nil" if the Optional is empty. For Optional<String> it returns the contained String directly (when present), for all other types it uses String(describing:).

StringProtocol

• quoted returns a quoted version of the string, with backslash-escaping for existing quotes and backslashes in the string. e.g. #"Hello, "Alex" \ "Alexis"."#.quoted -> #""Hello, \"Alex\" \\ \"Alexis\".""#