CollectionKit

A Swift package that provides a collection of useful data structures and extensions for working with collections in iOS, macOS, and tvOS applications.

Overview

CollectionKit extends Swift's collection types with additional functionality and provides specialized data structures for common programming needs. It includes efficient implementations of sets, queues, stacks, and more, along with convenient extensions for sequence and collection operations.

Data Structures

BitSet

A compact set of bits backed by a byte array, perfect for efficient boolean flag storage.

var bitSet = BitSet(bitsToSet: [0, 2, 5])
bitSet.setBit(at: 7)
print(bitSet.isBitSet(at: 2)) // true

OrderedSet

Maintains uniqueness of elements while preserving insertion order.

var orderedSet = OrderedSet<String>()
orderedSet.append("first")
orderedSet.append("second") 
orderedSet.append("first") // Won't be added again
print(orderedSet.array) // ["first", "second"]

PriorityQueue

A binary heap-based priority queue with customizable comparison.

var queue = PriorityQueue<Int>(>)
queue.add([7, 5, 99, 17])
print(queue.removeFirst()) // 99 (highest priority)

Queue & Stack

Standard FIFO queue and LIFO stack implementations.

var queue = Queue<String>()
queue.enqueue("first")
queue.enqueue("second")
print(queue.dequeue()) // "first"

var stack = Stack<Int>()
stack.push(1)
stack.push(2)
print(stack.pop()) // 2

SnapshotStack

A stack that can capture and restore snapshots of its state.

PointQuadTree

Spatial data structure for efficient 2D point storage and querying.

ArrayBuilder

Result builder for constructing arrays with a declarative syntax.

Collection Extensions

CollectionKit provides numerous extensions to make working with collections more convenient:

Sequence Extensions

• first(where:equals:) - Find elements by key path equality
• last(where:equals:) - Find last element by key path equality
• countWhere(_:) - Count elements matching a condition
• contains(where:equals:) - Check existence by key path equality
• sum() - Sum numeric sequences
• unique() - Remove duplicates
• takeWhile(_:) - Take elements while condition is true
• skipWhile(_:) - Skip elements while condition is true

Collection Extensions

• chunks(of:) - Split into chunks of specified size
• average() - Calculate average of numeric collections
• safeIndex(_:) - Safe index access
• index(of:where:equals:) - Find index by key path equality

Array Extensions

• removeFirst(where:) - Remove first matching element
• transformFirst(where:_:) - Transform first matching element
• splittingOffFirst(where:) - Split array at first match

License

CollectionKit is available under the BSD Zero Clause License. See the LICENSE file for more information.