1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
|
//===----------------------------------------------------------------------===//
//
// This source file is part of the Swift Collections open source project
//
// Copyright (c) 2022 - 2024 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See https://swift.org/LICENSE.txt for license information
//
//===----------------------------------------------------------------------===//
#if !COLLECTIONS_SINGLE_MODULE
import InternalCollectionsUtilities
#endif
extension TreeSet {
/// Returns a new set containing the elements of this set that do not occur
/// in the given other set.
///
/// var a: TreeSet = [1, 2, 3, 4]
/// let b: TreeSet = [0, 2, 4, 6]
/// let c = a.subtracting(b)
/// // `c` is some permutation of `[1, 3]`
///
/// - Parameter other: An arbitrary set of elements.
///
/// - Complexity: Expected complexity is O(`self.count`) in
/// the worst case, if `Element` properly implements hashing.
/// However, the implementation is careful to make the best use of
/// hash tree structure to minimize work when possible, e.g. by linking
/// parts of the input trees directly into the result.
@inlinable
public __consuming func subtracting(_ other: Self) -> Self {
_subtracting(other._root)
}
/// Returns a new set containing the elements of this set that do not occur
/// in the given keys view of a persistent dictionary.
///
/// var a: TreeSet = [1, 2, 3, 4]
/// let b: TreeDictionary = [0: "a", 2: "b", 4: "c", 6: "d"]
/// let c = a.subtracting(b.keys)
/// // `c` is some permutation of `[1, 3]`
///
/// - Parameter other: The keys view of a persistent dictionary.
///
/// - Complexity: Expected complexity is O(`self.count`) in
/// the worst case, if `Element` properly implements hashing.
/// However, the implementation is careful to make the best use of
/// hash tree structure to minimize work when possible, e.g. by linking
/// parts of the input trees directly into the result.
@inlinable
public __consuming func subtracting<V>(
_ other: TreeDictionary<Element, V>.Keys
) -> Self {
_subtracting(other._base._root)
}
@inlinable
internal __consuming func _subtracting<V>(
_ other: _HashNode<Element, V>
) -> Self {
guard let r = _root.subtracting(.top, other) else { return self }
return Self(_new: r)
}
/// Returns a new set containing the elements of this set that do not occur
/// in the given sequence.
///
/// var a: TreeSet = [1, 2, 3, 4]
/// let b = [0, 2, 4, 6]
/// let c = a.subtracting(b)
/// // `c` is some permutation of `[1, 3]`
///
/// - Parameter other: An arbitrary finite sequence.
///
/// - Complexity: O(*n*) where *n* is the number of elements in `other`,
/// as long as `Element` properly implements hashing.
@inlinable
public __consuming func subtracting(_ other: some Sequence<Element>) -> Self {
if let other = _specialize(other, for: Self.self) {
return subtracting(other)
}
guard let first = self.first else { return Self() }
if other._customContainsEquatableElement(first) != nil {
// Fast path: the sequence has fast containment checks.
return self.filter { !other.contains($0) }
}
var root = self._root
for item in other {
let hash = _Hash(item)
_ = root.remove(.top, item, hash)
}
return Self(_new: root)
}
}
|
