CHANGELOG.md

CHANGELOG

This project follows semantic versioning.

Unreleased

No new changes.

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1.0.0 - 2021-09-08

Changes

• Most sequence and collection types have been renamed, following a more consistent naming structure:
  • The Lazy prefix was dropped.
  • Either a Sequence or Collection suffix was added depending on whether or not the type is unconditionally a collection.
  • The base name was derived from the name of the method that produces it, including an argument label to disambiguate if necessary.

  Chain2              -> Chain2Sequence
  ChunkedBy           -> ChunkedByCollection
  ChunkedOn           -> ChunkedOnCollection
  ChunkedByCount      -> ChunksOfCountCollection
  Combinations        -> CombinationsSequence
  Cycle               -> CycledSequence
  FiniteCycle         -> CycledTimesCollection
  Indexed             -> IndexedCollection
  Intersperse         -> InterspersedSequence
  LazySplitSequence   -> SplitSequence
  LazySplitCollection -> SplitCollection
  Permutations        -> PermutationsSequence
  UniquePermutations  -> UniquePermutationsSequence
  Product2            -> Product2Sequence
  ExclusiveReductions -> ExclusiveReductionsSequence
  InclusiveReductions -> InclusiveReductionsSequence
  StrideSequence      -> StridingSequence
  StrideCollection    -> StridingCollection
  Uniqued             -> UniquedSequence
  Windows             -> WindowsOfCountCollection
  

• Types that can only be produced from a lazy sequence chain now unconditionally conform to LazySequenceProtocol and wrap the base sequence instead of the lazy wrapper, making some return types slightly simpler.
  • e.g. [1, 2, 3].lazy.reductions(+) now returns ExclusiveReductionsSequence<[Int]>, not ExclusiveReductionsSequence<LazySequence<[Int]>>.
  • This concerns JoinedByClosureSequence, JoinedByClosureCollection, ExclusiveReductionsSequence, InclusiveReductionsSequence.
• The generic parameters of the ExclusiveReductions type have been swapped, putting the base collection first and the result type second.
• The Indices associated type of IndexedCollection now matches Base.Indices.

Removals

• Previously deprecated type and method names have been removed:
  • The Chain type alias for Chain2Sequence
  • The chained(with:) method which was replaced with the chain(_:_:) free function
  • The LazyChunked and Chunked type aliases for ChunkedByCollection
  • The rotate(subrange:at:) and rotate(at:) methods which were renamed to rotate(subrange:toStartAt:) and rotate(toStartAt:) respectively

Fixes

• The StridingSequence and StridingCollection types now conditionally conform to LazySequenceProtocol, allowing the striding(by:) method to properly propagate laziness in a lazy sequence chain.
• Fixed chunked(by:) to always compare two consecutive elements rather than each element with the first element of the current chunk. (#162)

The 1.0.0 release includes contributions from iainsmith, mdznr, and timvermeulen. Thank you!

0.2.1 - 2021-06-01

Additions

Expanded versatility for two existing operations:

• A series of joined(by:) overloads concatenate a sequence of sequences using an element or a collection, either passed in or generated from consecutive elements via a closure. (#138)
• Additional trimming(while:) methods for trimming only the start or end of a collection, as well as mutating versions of all three variants. (#104)

The 0.2.1 release includes contributions from fedeci and timvermeulen. Thank you!

0.2.0 - 2021-05-17

Additions

Two new additions to the list of algorithms:

• adjacentPairs() lazily iterates over tuples of adjacent elements of a sequence. (#119)
• minAndMax() finds both the smallest and largest elements of a sequence in a single pass. (#90)

Changes

• When calling chunked(on:), the resulting collection has an element type of (Subject, SubSequence) instead of just SubSequence, making the subject value available when iterating.

  let numbers = [5, 6, -3, -9, -11, 2, 7, 6]
  for (signum, values) in numbers.chunked(on: { $0.signum() }) {
      print(signum, values)
  }
  // 1 [5, 6]
  // -1 [-3, -9, -11]
  // 1 [2, 7, 6]

Fixes

• Improvements to the documentation and PR templates.

The 0.2.0 release includes contributions from CTMacUser, LemonSpike, mpangburn, and natecook1000. Thank you!

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0.1.1 - 2021-04-14

Fixes

• Product2 associated type inference error in release build (#130)

0.1.0 - 2021-04-13

Additions

• The compacted() method lazily finds the non-nil elements of a sequence or collection (#112).

Changes

• The uniqued() method now lazily computes the unique elements of a sequence or a collection (#71). Pass this resulting sequence to an Array initializer to recover the behavior of the previous release.
• Calling cycled(times:) now returns a new FiniteCycle type, which has the same conformances as its underlying collection (#106).
• The base collections of the sequence and collection wrapper types are no longer public (#85, #125), and the wrapper types no longer conform to the Equatable or Hashable protocols (#124). If you need those conformances, convert the wrapper type to an Array or other collection currrency type before storing. Please file an issue if these changes pose a problem for your use case.

The 0.1.0 release includes contributions from LemonSpike, LucianoPAlmeida, natecook1000, and timvermeulen. Thank you!

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0.0.4 - 2021-03-29

Additions

More new algorithms to join the party:

• A lazy version of the standard library's two split methods. (#78)
• firstNonNil(_:) returns the first non-nil element from an optional-generating transform. (#31)
• uniquePermutations() skips duplicates when generating permutations of a collection. (#91)
• The reductions methods return all the in-between states of reducing a sequence or collection. (#46)

Fixes

• Methods and computed properties are more consistently marked as inlinable, resolving a performance regression.
• The Stride type now efficiently calculates distances between positions, supported by the underlying collection.
• Better test coverage and improved diagnostics for comparing sequences.
• Fixed links and improved documentation.

The 0.0.4 release includes contributions from bjhomer, danielctull, hashemi, karwa, kylemacomber, LucianoPAlmeida, mdznr, natecook1000, ollieatkinson, Qata, timvermeulen, and toddthomas. Thank you!

0.0.3 - 2021-02-26

Additions

An exciting group of new algorithms, contributed by the community:

• trimming(while:) returns a subsequence of a bidirectional collection with the matching elements removed from the start and end. (#4)
• min(ofCount:) and max(ofCount:) find the smallest or largest elements in a collection. (#9, #77)
• windows(ofCount:) lets you iterate over all the overlapping subsequences of a particular length. (#20)
• striding(by:) iterates over every nth element of a sequence or collection. (#24)
• interspersed(with:) places a new element between every pair of elements in a sequence or collection. (#35)
• chunks(ofCount:) breaks a collection into subsequences of the given number of elements. (#54)
• suffix(while:) matches the standard library's prefix(while:), by returning the suffix of all matching elements from a bidirectional collection. (#65)
• Variations of combinations(ofCount:) and permutations(ofCount:) that take a range expression as a parameter, returning combinations and permutations of multiple lengths. (#51, #56)

Changes

• The LazyChunked type now precomputes its startIndex, making performance more predictable when using the collection.

Fixes

• randomSample(count:) no longer traps in rare circumstances.
• Index calculations have been improved in a variety of collection wrappers.
• A variety of documentation improvements and corrections.

The 0.0.3 release includes contributions from benrimmington, danielctull, dhruvshah8, karwa, LucianoPAlmeida, markuswntr, mdznr, michiboo, natecook1000, ollieatkinson, rakaramos, rockbruno, Roshankumar350, sidepelican, and timvermeulen. Thank you!

0.0.2 - 2020-10-23

Changes

• The rotate(at:) method has been updated to rotate(toStartAt:), with the old name deprecated.
• The chained(with:) method has been changed to the free function chain(_:_:), with the old version deprecated.
• Algorithms now uses RealModule from the swift-numerics package for its cross-platform elementary functions.
• Sequence/collection wrapper types, like Permutations and Indexed, now have conformance to the lazy protocols, so that any following operations maintain their laziness.

Fixes

• Algorithms now builds under SwiftPM on Windows.
• A wide variety of errors, misspellings, and ommissions in the documentation and guides have been fixed.
• Index/distance calculations for the Product2 and Chain types have been corrected.
• Calling stablePartition(subrange:by:) now correctly uses the subrange's length instead of the whole collection.

The 0.0.2 release includes contributions from AustinConlon, egorzhdan, IanKeen, iSame7, karwa, kylemacomber, natecook1000, nordicio, pmtao, schlagelk, stephentyrone, and timvermeulen. Thank you!

0.0.1 - 2020-10-07

• Swift Algorithms initial release.

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