mirror of
https://github.com/apple/swift.git
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481bcabcba
- `separator` label for first argument of `split` - `join` and related types are renamed to `joined`
784 lines
25 KiB
Swift
784 lines
25 KiB
Swift
//===----------------------------------------------------------------------===//
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//
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// This source file is part of the Swift.org open source project
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//
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// Copyright (c) 2014 - 2016 Apple Inc. and the Swift project authors
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// Licensed under Apache License v2.0 with Runtime Library Exception
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//
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// See http://swift.org/LICENSE.txt for license information
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// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
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//
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//===----------------------------------------------------------------------===//
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/// A type that provides subscript access to its elements.
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///
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/// - Important: In most cases, it's best to ignore this protocol and use
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/// `CollectionType` instead, as it has a more complete interface.
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public protocol Indexable {
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// This protocol is almost an implementation detail of the standard
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// library; it is used to deduce things like the `SubSequence` and
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// `Iterator` type from a minimal collection, but it is also used in
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// exposed places like as a constraint on `IndexingIterator`.
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/// A type that represents a valid position in the collection.
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///
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/// Valid indices consist of the position of every element and a
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/// "past the end" position that's not valid for use as a subscript.
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associatedtype Index : ForwardIndex
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/// The position of the first element in a non-empty collection.
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///
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/// In an empty collection, `startIndex == endIndex`.
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///
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/// - Complexity: O(1)
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var startIndex: Index { get }
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/// The collection's "past the end" position.
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///
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/// `endIndex` is not a valid argument to `subscript`, and is always
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/// reachable from `startIndex` by zero or more applications of
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/// `successor()`.
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///
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/// - Complexity: O(1)
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var endIndex: Index { get }
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// The declaration of _Element and subscript here is a trick used to
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// break a cyclic conformance/deduction that Swift can't handle. We
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// need something other than a Collection.Iterator.Element that can
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// be used as IndexingIterator<T>'s Element. Here we arrange for
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// the Collection itself to have an Element type that's deducible from
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// its subscript. Ideally we'd like to constrain this Element to be the same
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// as Collection.Iterator.Element (see below), but we have no way of
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// expressing it today.
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associatedtype _Element
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/// Returns the element at the given `position`.
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///
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/// - Complexity: O(1)
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subscript(position: Index) -> _Element { get }
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}
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/// A type that supports subscript assignment to a mutable collection.
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public protocol MutableIndexable {
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associatedtype Index : ForwardIndex
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var startIndex: Index { get }
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var endIndex: Index { get }
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associatedtype _Element
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subscript(position: Index) -> _Element { get set }
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}
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/// The iterator used for collections that don't specify one.
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public struct IndexingIterator<Elements : Indexable>
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: IteratorProtocol, Sequence {
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/// Create an *iterator* over the given collection.
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public /// @testable
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init(_elements: Elements) {
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self._elements = _elements
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self._position = _elements.startIndex
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}
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/// Advance to the next element and return it, or `nil` if no next
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/// element exists.
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///
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/// - Precondition: No preceding call to `self.next()` has returned `nil`.
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public mutating func next() -> Elements._Element? {
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if _position == _elements.endIndex { return nil }
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let element = _elements[_position]
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_position._successorInPlace()
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return element
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}
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internal let _elements: Elements
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internal var _position: Elements.Index
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}
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/// A multi-pass sequence with addressable positions.
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///
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/// Positions are represented by an associated `Index` type. Whereas
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/// an arbitrary sequence may be consumed as it is traversed, a
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/// collection is multi-pass: any element may be revisited merely by
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/// saving its index.
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///
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/// The sequence view of the elements is identical to the collection
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/// view. In other words, the following code binds the same series of
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/// values to `x` as does `for x in self {}`:
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///
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/// for i in startIndex..<endIndex {
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/// let x = self[i]
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/// }
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public protocol Collection : Indexable, Sequence {
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/// A type that provides the sequence's iteration interface and
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/// encapsulates its iteration state.
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///
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/// By default, a `Collection` satisfies `Sequence` by
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/// supplying a `IndexingIterator` as its associated `Iterator`
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/// type.
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associatedtype Iterator : IteratorProtocol = IndexingIterator<Self>
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// FIXME: Needed here so that the Iterator is properly deduced from
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// a custom iterator() function. Otherwise we get an
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// IndexingIterator. <rdar://problem/21539115>
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func iterator() -> Iterator
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// FIXME: should be constrained to Collection
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// (<rdar://problem/20715009> Implement recursive protocol
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// constraints)
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/// A `Sequence` that can represent a contiguous subrange of `self`'s
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/// elements.
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///
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/// - Note: This associated type appears as a requirement in
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/// `Sequence`, but is restated here with stricter
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/// constraints: in a `Collection`, the `SubSequence` should
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/// also be a `Collection`.
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associatedtype SubSequence : Indexable, Sequence = Slice<Self>
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/// Returns the element at the given `position`.
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subscript(position: Index) -> Iterator.Element { get }
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/// Returns a collection representing a contiguous sub-range of
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/// `self`'s elements.
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///
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/// - Complexity: O(1)
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subscript(bounds: Range<Index>) -> SubSequence { get }
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/// Returns `self[startIndex..<end]`
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///
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/// - Complexity: O(1)
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@warn_unused_result
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func prefix(upTo end: Index) -> SubSequence
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/// Returns `self[start..<endIndex]`
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///
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/// - Complexity: O(1)
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@warn_unused_result
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func suffix(from start: Index) -> SubSequence
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/// Returns `prefix(upTo: position.successor())`
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///
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/// - Complexity: O(1)
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@warn_unused_result
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func prefix(through position: Index) -> SubSequence
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/// Returns `true` iff `self` is empty.
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var isEmpty: Bool { get }
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/// Returns the number of elements.
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///
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/// - Complexity: O(1) if `Index` conforms to `RandomAccessIndex`;
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/// O(N) otherwise.
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var count: Index.Distance { get }
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// The following requirement enables dispatching for indexOf when
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// the element type is Equatable.
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/// Returns `Optional(Optional(index))` if an element was found;
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/// `nil` otherwise.
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///
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/// - Complexity: O(N).
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@warn_unused_result
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func _customIndexOfEquatableElement(element: Iterator.Element) -> Index??
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/// Returns the first element of `self`, or `nil` if `self` is empty.
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var first: Iterator.Element? { get }
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}
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/// Supply the default `iterator()` method for `Collection` models
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/// that accept the default associated `Iterator`,
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/// `IndexingIterator<Self>`.
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extension Collection where Iterator == IndexingIterator<Self> {
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public func iterator() -> IndexingIterator<Self> {
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return IndexingIterator(_elements: self)
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}
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}
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/// Supply the default "slicing" `subscript` for `Collection` models
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/// that accept the default associated `SubSequence`, `Slice<Self>`.
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extension Collection where SubSequence == Slice<Self> {
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public subscript(bounds: Range<Index>) -> Slice<Self> {
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Index._failEarlyRangeCheck2(
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rangeStart: bounds.startIndex,
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rangeEnd: bounds.endIndex,
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boundsStart: startIndex,
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boundsEnd: endIndex)
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return Slice(_base: self, bounds: bounds)
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}
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}
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extension Collection where SubSequence == Self {
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/// If `!self.isEmpty`, remove the first element and return it, otherwise
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/// return `nil`.
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///
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/// - Complexity: O(1)
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@warn_unused_result
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public mutating func popFirst() -> Iterator.Element? {
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guard !isEmpty else { return nil }
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let element = first!
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self = self[startIndex.successor()..<endIndex]
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return element
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}
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}
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extension Collection where
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SubSequence == Self, Index : BidirectionalIndex {
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/// If `!self.isEmpty`, remove the last element and return it, otherwise
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/// return `nil`.
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///
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/// - Complexity: O(1)
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@warn_unused_result
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public mutating func popLast() -> Iterator.Element? {
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guard !isEmpty else { return nil }
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let element = last!
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self = self[startIndex..<endIndex.predecessor()]
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return element
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}
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}
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/// Default implementations of core requirements
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extension Collection {
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/// Returns `true` iff `self` is empty.
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///
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/// - Complexity: O(1)
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public var isEmpty: Bool {
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return startIndex == endIndex
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}
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/// Returns the first element of `self`, or `nil` if `self` is empty.
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///
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/// - Complexity: O(1)
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public var first: Iterator.Element? {
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// NB: Accessing `startIndex` may not be O(1) for some lazy collections,
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// so instead of testing `isEmpty` and then returning the first element,
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// we'll just rely on the fact that the generator always yields the
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// first element first.
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var i = iterator()
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return i.next()
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}
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/// Returns a value less than or equal to the number of elements in
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/// `self`, *nondestructively*.
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///
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/// - Complexity: O(`count`).
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public var underestimatedCount: Int {
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return numericCast(count)
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}
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/// Returns the number of elements.
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///
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/// - Complexity: O(1) if `Index` conforms to `RandomAccessIndex`;
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/// O(N) otherwise.
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public var count: Index.Distance {
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return startIndex.distance(to: endIndex)
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}
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/// Customization point for `Sequence.indexOf()`.
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///
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/// Define this method if the collection can find an element in less than
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/// O(N) by exploiting collection-specific knowledge.
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///
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/// - Returns: `nil` if a linear search should be attempted instead,
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/// `Optional(nil)` if the element was not found, or
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/// `Optional(Optional(index))` if an element was found.
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///
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/// - Complexity: O(`count`).
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@warn_unused_result
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public // dispatching
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func _customIndexOfEquatableElement(_: Iterator.Element) -> Index?? {
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return nil
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}
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}
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//===----------------------------------------------------------------------===//
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// Default implementations for Collection
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//===----------------------------------------------------------------------===//
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extension Collection {
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/// Returns an `Array` containing the results of mapping `transform`
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/// over `self`.
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///
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/// - Complexity: O(N).
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@warn_unused_result
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public func map<T>(
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@noescape transform: (Iterator.Element) throws -> T
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) rethrows -> [T] {
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let count: Int = numericCast(self.count)
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if count == 0 {
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return []
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}
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var result = ContiguousArray<T>()
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result.reserveCapacity(count)
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var i = self.startIndex
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for _ in 0..<count {
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result.append(try transform(self[i]))
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i = i.successor()
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}
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_expectEnd(i, self)
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return Array(result)
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}
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/// Returns a subsequence containing all but the first `n` elements.
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///
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/// - Precondition: `n >= 0`
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/// - Complexity: O(`n`)
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@warn_unused_result
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public func dropFirst(n: Int) -> SubSequence {
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_precondition(n >= 0, "Can't drop a negative number of elements from a collection")
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let start = startIndex.advanced(by: numericCast(n), limit: endIndex)
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return self[start..<endIndex]
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}
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/// Returns a subsequence containing all but the last `n` elements.
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///
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/// - Precondition: `n >= 0`
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/// - Complexity: O(`self.count`)
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@warn_unused_result
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public func dropLast(n: Int) -> SubSequence {
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_precondition(
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n >= 0, "Can't drop a negative number of elements from a collection")
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let amount = Swift.max(0, numericCast(count) - n)
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let end = startIndex.advanced(by: numericCast(amount), limit: endIndex)
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return self[startIndex..<end]
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}
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/// Returns a subsequence, up to `maxLength` in length, containing the
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/// initial elements.
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///
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/// If `maxLength` exceeds `self.count`, the result contains all
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/// the elements of `self`.
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///
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/// - Precondition: `maxLength >= 0`
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/// - Complexity: O(`maxLength`)
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@warn_unused_result
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public func prefix(maxLength: Int) -> SubSequence {
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_precondition(
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maxLength >= 0,
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"Can't take a prefix of negative length from a collection")
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let end = startIndex.advanced(by: numericCast(maxLength), limit: endIndex)
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return self[startIndex..<end]
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}
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/// Returns a slice, up to `maxLength` in length, containing the
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/// final elements of `self`.
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///
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/// If `maxLength` exceeds `s.count`, the result contains all
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/// the elements of `self`.
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///
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/// - Precondition: `maxLength >= 0`
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/// - Complexity: O(`self.count`)
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@warn_unused_result
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public func suffix(maxLength: Int) -> SubSequence {
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_precondition(
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maxLength >= 0,
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"Can't take a suffix of negative length from a collection")
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let amount = Swift.max(0, numericCast(count) - maxLength)
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let start = startIndex.advanced(by: numericCast(amount), limit: endIndex)
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return self[start..<endIndex]
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}
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/// Returns `self[startIndex..<end]`
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///
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/// - Complexity: O(1)
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@warn_unused_result
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public func prefix(upTo end: Index) -> SubSequence {
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return self[startIndex..<end]
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}
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/// Returns `self[start..<endIndex]`
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///
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/// - Complexity: O(1)
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@warn_unused_result
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public func suffix(from start: Index) -> SubSequence {
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return self[start..<endIndex]
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}
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/// Returns `prefix(upTo: position.successor())`
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///
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/// - Complexity: O(1)
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@warn_unused_result
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public func prefix(through position: Index) -> SubSequence {
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return prefix(upTo: position.successor())
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}
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/// Returns the maximal `SubSequence`s of `self`, in order, that
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/// don't contain elements satisfying the predicate `isSeparator`.
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///
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/// - Parameter maxSplits: The maximum number of `SubSequence`s to
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/// return, minus 1.
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/// If `maxSplits + 1` `SubSequence`s are returned, the last one is
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/// a suffix of `self` containing *all* the elements of `self` following the
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/// last split point.
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/// The default value is `Int.max`.
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///
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/// - Parameter omittingEmptySubsequences: If `false`, an empty `SubSequence`
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/// is produced in the result for each pair of consecutive elements
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/// satisfying `isSeparator`.
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/// The default value is `true`.
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///
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/// - Precondition: `maxSplits >= 0`
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@warn_unused_result
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public func split(
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maxSplits maxSplits: Int = Int.max,
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omittingEmptySubsequences: Bool = true,
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@noescape isSeparator: (Iterator.Element) throws -> Bool
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) rethrows -> [SubSequence] {
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_precondition(maxSplits >= 0, "Must take zero or more splits")
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var result: [SubSequence] = []
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var subSequenceStart: Index = startIndex
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func appendSubsequence(end end: Index) -> Bool {
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if subSequenceStart == end && omittingEmptySubsequences {
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return false
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}
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result.append(self[subSequenceStart..<end])
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return true
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}
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if maxSplits == 0 || isEmpty {
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appendSubsequence(end: endIndex)
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return result
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}
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var subSequenceEnd = subSequenceStart
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let cachedEndIndex = endIndex
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while subSequenceEnd != cachedEndIndex {
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if try isSeparator(self[subSequenceEnd]) {
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let didAppend = appendSubsequence(end: subSequenceEnd)
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subSequenceEnd._successorInPlace()
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subSequenceStart = subSequenceEnd
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if didAppend && result.count == maxSplits {
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break
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}
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continue
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}
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subSequenceEnd._successorInPlace()
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}
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if subSequenceStart != cachedEndIndex || !omittingEmptySubsequences {
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result.append(self[subSequenceStart..<cachedEndIndex])
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}
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return result
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}
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}
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extension Collection where Iterator.Element : Equatable {
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/// Returns the maximal `SubSequence`s of `self`, in order, around a
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/// `separator` element.
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///
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/// - Parameter maxSplits: The maximum number of `SubSequence`s to
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/// return, minus 1.
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/// If `maxSplits + 1` `SubSequence`s are returned, the last one is
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/// a suffix of `self` containing *all* the elements of `self` following the
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/// last split point.
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/// The default value is `Int.max`.
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///
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/// - Parameter omittingEmptySubsequences: If `false`, an empty `SubSequence`
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/// is produced in the result for each pair of consecutive elements
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/// equal to `separator`.
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/// The default value is `true`.
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///
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/// - Precondition: `maxSplits >= 0`
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@warn_unused_result
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public func split(
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separator separator: Iterator.Element,
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maxSplits: Int = Int.max,
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omittingEmptySubsequences: Bool = true
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) -> [SubSequence] {
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return split(
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maxSplits: maxSplits,
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omittingEmptySubsequences: omittingEmptySubsequences,
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isSeparator: { $0 == separator })
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}
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}
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extension Collection where Index : BidirectionalIndex {
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/// Returns a subsequence containing all but the last `n` elements.
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///
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/// - Precondition: `n >= 0`
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/// - Complexity: O(`n`)
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@warn_unused_result
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public func dropLast(n: Int) -> SubSequence {
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_precondition(
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n >= 0, "Can't drop a negative number of elements from a collection")
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let end = endIndex.advanced(by: numericCast(-n), limit: startIndex)
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return self[startIndex..<end]
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}
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|
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/// Returns a slice, up to `maxLength` in length, containing the
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/// final elements of `self`.
|
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///
|
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/// If `maxLength` exceeds `s.count`, the result contains all
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/// the elements of `self`.
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///
|
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/// - Precondition: `maxLength >= 0`
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/// - Complexity: O(`maxLength`)
|
|
@warn_unused_result
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public func suffix(maxLength: Int) -> SubSequence {
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_precondition(
|
|
maxLength >= 0,
|
|
"Can't take a suffix of negative length from a collection")
|
|
let start = endIndex.advanced(by: numericCast(-maxLength), limit: startIndex)
|
|
return self[start..<endIndex]
|
|
}
|
|
}
|
|
|
|
extension Collection where SubSequence == Self {
|
|
/// Remove the element at `startIndex` and return it.
|
|
///
|
|
/// - Complexity: O(1)
|
|
/// - Precondition: `!self.isEmpty`.
|
|
public mutating func removeFirst() -> Iterator.Element {
|
|
_precondition(!isEmpty, "can't remove items from an empty collection")
|
|
let element = first!
|
|
self = self[startIndex.successor()..<endIndex]
|
|
return element
|
|
}
|
|
|
|
/// Remove the first `n` elements.
|
|
///
|
|
/// - Complexity:
|
|
/// - O(1) if `Index` conforms to `RandomAccessIndex`
|
|
/// - O(n) otherwise
|
|
/// - Precondition: `n >= 0 && self.count >= n`.
|
|
public mutating func removeFirst(n: Int) {
|
|
if n == 0 { return }
|
|
_precondition(n >= 0, "number of elements to remove should be non-negative")
|
|
_precondition(count >= numericCast(n),
|
|
"can't remove more items from a collection than it contains")
|
|
self = self[startIndex.advanced(by: numericCast(n))..<endIndex]
|
|
}
|
|
}
|
|
|
|
extension Collection
|
|
where
|
|
SubSequence == Self,
|
|
Index : BidirectionalIndex {
|
|
|
|
/// Remove an element from the end.
|
|
///
|
|
/// - Complexity: O(1)
|
|
/// - Precondition: `!self.isEmpty`
|
|
public mutating func removeLast() -> Iterator.Element {
|
|
let element = last!
|
|
self = self[startIndex..<endIndex.predecessor()]
|
|
return element
|
|
}
|
|
|
|
/// Remove the last `n` elements.
|
|
///
|
|
/// - Complexity:
|
|
/// - O(1) if `Index` conforms to `RandomAccessIndex`
|
|
/// - O(n) otherwise
|
|
/// - Precondition: `n >= 0 && self.count >= n`.
|
|
public mutating func removeLast(n: Int) {
|
|
if n == 0 { return }
|
|
_precondition(n >= 0, "number of elements to remove should be non-negative")
|
|
_precondition(count >= numericCast(n),
|
|
"can't remove more items from a collection than it contains")
|
|
self = self[startIndex..<endIndex.advanced(by: numericCast(-n))]
|
|
}
|
|
}
|
|
|
|
extension Sequence
|
|
where Self : _ArrayProtocol, Self.Element == Self.Iterator.Element {
|
|
// A fast implementation for when you are backed by a contiguous array.
|
|
public func _initializeTo(ptr: UnsafeMutablePointer<Iterator.Element>)
|
|
-> UnsafeMutablePointer<Iterator.Element> {
|
|
let s = self._baseAddressIfContiguous
|
|
if s != nil {
|
|
let count = self.count
|
|
ptr.initializeFrom(s, count: count)
|
|
_fixLifetime(self._owner)
|
|
return ptr + count
|
|
} else {
|
|
var p = ptr
|
|
for x in self {
|
|
p.initializePointee(x)
|
|
p += 1
|
|
}
|
|
return p
|
|
}
|
|
}
|
|
}
|
|
|
|
extension Collection {
|
|
public func _preprocessingPass<R>(@noescape preprocess: () -> R) -> R? {
|
|
return preprocess()
|
|
}
|
|
}
|
|
|
|
/// A *collection* that supports subscript assignment.
|
|
///
|
|
/// For any instance `a` of a type conforming to
|
|
/// `MutableCollection`, :
|
|
///
|
|
/// a[i] = x
|
|
/// let y = a[i]
|
|
///
|
|
/// is equivalent to:
|
|
///
|
|
/// a[i] = x
|
|
/// let y = x
|
|
///
|
|
public protocol MutableCollection : MutableIndexable, Collection {
|
|
// FIXME: should be constrained to MutableCollection
|
|
// (<rdar://problem/20715009> Implement recursive protocol
|
|
// constraints)
|
|
associatedtype SubSequence : Collection /*: MutableCollection*/
|
|
= MutableSlice<Self>
|
|
|
|
/// Access the element at `position`.
|
|
///
|
|
/// - Precondition: `position` indicates a valid position in `self` and
|
|
/// `position != endIndex`.
|
|
///
|
|
/// - Complexity: O(1)
|
|
subscript(position: Index) -> Iterator.Element {get set}
|
|
|
|
/// Returns a collection representing a contiguous sub-range of
|
|
/// `self`'s elements.
|
|
///
|
|
/// - Complexity: O(1) for the getter, O(`bounds.count`) for the setter.
|
|
subscript(bounds: Range<Index>) -> SubSequence {get set}
|
|
|
|
/// Call `body(p)`, where `p` is a pointer to the collection's
|
|
/// mutable contiguous storage. If no such storage exists, it is
|
|
/// first created. If the collection does not support an internal
|
|
/// representation in a form of mutable contiguous storage, `body` is not
|
|
/// called and `nil` is returned.
|
|
///
|
|
/// Often, the optimizer can eliminate bounds- and uniqueness-checks
|
|
/// within an algorithm, but when that fails, invoking the
|
|
/// same algorithm on `body`\ 's argument lets you trade safety for
|
|
/// speed.
|
|
mutating func _withUnsafeMutableBufferPointerIfSupported<R>(
|
|
@noescape body: (UnsafeMutablePointer<Iterator.Element>, Int) throws -> R
|
|
) rethrows -> R?
|
|
// FIXME: the signature should use UnsafeMutableBufferPointer, but the
|
|
// compiler can't handle that.
|
|
//
|
|
// <rdar://problem/21933004> Restore the signature of
|
|
// _withUnsafeMutableBufferPointerIfSupported() that mentions
|
|
// UnsafeMutableBufferPointer
|
|
}
|
|
|
|
extension MutableCollection {
|
|
public mutating func _withUnsafeMutableBufferPointerIfSupported<R>(
|
|
@noescape body: (UnsafeMutablePointer<Iterator.Element>, Int) throws -> R
|
|
) rethrows -> R? {
|
|
return nil
|
|
}
|
|
|
|
public subscript(bounds: Range<Index>) -> MutableSlice<Self> {
|
|
get {
|
|
Index._failEarlyRangeCheck2(
|
|
rangeStart: bounds.startIndex,
|
|
rangeEnd: bounds.endIndex,
|
|
boundsStart: startIndex,
|
|
boundsEnd: endIndex)
|
|
return MutableSlice(_base: self, bounds: bounds)
|
|
}
|
|
set {
|
|
_writeBackMutableSlice(&self, bounds: bounds, slice: newValue)
|
|
}
|
|
}
|
|
}
|
|
|
|
internal func _writeBackMutableSlice<
|
|
C : MutableCollection,
|
|
Slice_ : Collection
|
|
where
|
|
C._Element == Slice_.Iterator.Element,
|
|
C.Index == Slice_.Index
|
|
>(inout self_: C, bounds: Range<C.Index>, slice: Slice_) {
|
|
C.Index._failEarlyRangeCheck2(
|
|
rangeStart: bounds.startIndex,
|
|
rangeEnd: bounds.endIndex,
|
|
boundsStart: self_.startIndex,
|
|
boundsEnd: self_.endIndex)
|
|
// FIXME(performance): can we use
|
|
// _withUnsafeMutableBufferPointerIfSupported? Would that create inout
|
|
// aliasing violations if the newValue points to the same buffer?
|
|
|
|
var selfElementIndex = bounds.startIndex
|
|
let selfElementsEndIndex = bounds.endIndex
|
|
var newElementIndex = slice.startIndex
|
|
let newElementsEndIndex = slice.endIndex
|
|
|
|
while selfElementIndex != selfElementsEndIndex &&
|
|
newElementIndex != newElementsEndIndex {
|
|
|
|
self_[selfElementIndex] = slice[newElementIndex]
|
|
selfElementIndex._successorInPlace()
|
|
newElementIndex._successorInPlace()
|
|
}
|
|
|
|
_precondition(
|
|
selfElementIndex == selfElementsEndIndex,
|
|
"Cannot replace a slice of a MutableCollection with a slice of a larger size")
|
|
_precondition(
|
|
newElementIndex == newElementsEndIndex,
|
|
"Cannot replace a slice of a MutableCollection with a slice of a smaller size")
|
|
}
|
|
|
|
@available(*, unavailable, message="Bit enum has been deprecated. Please use Int instead.")
|
|
public enum Bit {}
|
|
|
|
@available(*, unavailable, renamed="IndexingIterator")
|
|
public struct IndexingGenerator<Elements : Indexable> {}
|
|
|
|
@available(*, unavailable, renamed="Collection")
|
|
public typealias CollectionType = Collection
|
|
|
|
extension Collection {
|
|
@available(*, unavailable, renamed="Iterator")
|
|
public typealias Generator = Iterator
|
|
|
|
@available(*, unavailable, renamed="iterator")
|
|
public func generate() -> Iterator {
|
|
fatalError("unavailable function can't be called")
|
|
}
|
|
|
|
@available(*, unavailable, message="Removed in Swift 3. Please use underestimatedCount peoperty.")
|
|
public func underestimateCount() -> Int {
|
|
fatalError("unavailable function can't be called")
|
|
}
|
|
|
|
@available(*, unavailable, message="Please use split(_:omittingEmptySubsequences:isSeparator:) instead")
|
|
public func split(
|
|
maxSplit: Int = Int.max,
|
|
allowEmptySlices: Bool = false,
|
|
@noescape isSeparator: (Iterator.Element) throws -> Bool
|
|
) rethrows -> [SubSequence] {
|
|
fatalError("unavailable function can't be called")
|
|
}
|
|
}
|
|
|
|
extension Collection where Iterator.Element : Equatable {
|
|
@available(*, unavailable, message="Please use split(separator:maxSplits:omittingEmptySubsequences:) instead")
|
|
public func split(
|
|
separator: Iterator.Element,
|
|
maxSplit: Int = Int.max,
|
|
allowEmptySlices: Bool = false
|
|
) -> [SubSequence] {
|
|
fatalError("unavailable function can't be called")
|
|
}
|
|
}
|
|
@available(*, unavailable, renamed="MutableCollection")
|
|
public typealias MutableCollectionType = MutableCollection
|
|
|
|
@available(*, unavailable, message="PermutationGenerator has been removed in Swift 3")
|
|
public struct PermutationGenerator<C : Collection, Indices : Sequence> {}
|
|
|
|
@available(*, unavailable, message="Please use 'Collection where SubSequence : MutableCollection'")
|
|
public typealias MutableSliceable = Collection
|