struct PermutationGenerator<C : CollectionType, Indices : SequenceType where C.Index == Indices.Generator.Element>
Inheritance |
GeneratorType, SequenceType
View Protocol Hierarchy →
|
---|---|
Associated Types | |
Import | import Swift |
Initializers
Construct a generator over a permutation of elements
given
by indices
.
Requires: elements[i]
is valid for every i
in indices
.
Declaration
init(elements: C, indices: Indices)
Instance Variables
A sequence containing the same elements as a Base
sequence,
but on which some operations such as map
and filter
are
implemented lazily.
See Also: LazySequenceType
, LazySequence
Declaration
var lazy: LazySequence<PermutationGenerator<C, Indices>> { get }
Declared In
SequenceType
Instance Methods
Returns true
iff an element in self
satisfies predicate
.
Declaration
func contains(@noescape predicate: (C.Generator.Element) throws -> Bool) rethrows -> Bool
Declared In
SequenceType
Returns a subsequence containing all but the first element.
Complexity: O(1)
Declaration
func dropFirst() -> PermutationGenerator<C, Indices>.SubSequence
Declared In
SequenceType
Returns a subsequence containing all but the first n
elements.
Requires: n >= 0
Complexity: O(n
)
Declaration
func dropFirst(n: Int) -> AnySequence<C.Generator.Element>
Declared In
SequenceType
Returns a subsequence containing all but the last element.
Requires: self
is a finite sequence.
Complexity: O(self.count
)
Declaration
func dropLast() -> PermutationGenerator<C, Indices>.SubSequence
Declared In
SequenceType
Returns a subsequence containing all but the last n
elements.
Requires: self
is a finite collection.
Requires: n >= 0
Complexity: O(self.count
)
Declaration
func dropLast(n: Int) -> AnySequence<C.Generator.Element>
Declared In
SequenceType
Returns true
iff self
and other
contain equivalent elements, using
isEquivalent
as the equivalence test.
Requires: isEquivalent
is an
equivalence relation.
Declaration
func elementsEqual<OtherSequence : SequenceType where OtherSequence.Generator.Element == Generator.Element>(other: OtherSequence, @noescape isEquivalent: (C.Generator.Element, C.Generator.Element) throws -> Bool) rethrows -> Bool
Declared In
SequenceType
Returns a lazy SequenceType
containing pairs (n, x), where
ns are consecutive Int
s starting at zero, and xs are
the elements of base
:
> for (n, c) in "Swift".characters.enumerate() {
print("\(n): '\(c)'")
}
0: 'S'
1: 'w'
2: 'i'
3: 'f'
4: 't'
Declaration
func enumerate() -> EnumerateSequence<PermutationGenerator<C, Indices>>
Declared In
SequenceType
Returns an Array
containing the elements of self
,
in order, that satisfy the predicate includeElement
.
Declaration
func filter(@noescape includeElement: (C.Generator.Element) throws -> Bool) rethrows -> [C.Generator.Element]
Declared In
SequenceType
Returns an Array
containing the non-nil results of mapping
transform
over self
.
Complexity: O(M + N), where M is the length of self
and N is the length of the result.
Declaration
func flatMap<T>(@noescape transform: (C.Generator.Element) throws -> T?) rethrows -> [T]
Declared In
SequenceType
Returns an Array
containing the concatenated results of mapping
transform
over self
.
s.flatMap(transform)
is equivalent to
Array(s.map(transform).flatten())
Complexity: O(M + N), where M is the length of self
and N is the length of the result.
Declaration
func flatMap<S : SequenceType>(transform: (C.Generator.Element) throws -> S) rethrows -> [S.Generator.Element]
Declared In
SequenceType
Call body
on each element in self
in the same order as a
for-in loop.
sequence.forEach {
// body code
}
is similar to:
for element in sequence {
// body code
}
Note: You cannot use the break
or continue
statement to exit the
current call of the body
closure or skip subsequent calls.
Note: Using the return
statement in the body
closure will only
exit from the current call to body
, not any outer scope, and won't
skip subsequent calls.
Complexity: O(self.count
)
Declaration
func forEach(@noescape body: (C.Generator.Element) throws -> Void) rethrows
Declared In
SequenceType
Returns true
iff self
precedes other
in a lexicographical
("dictionary") ordering, using isOrderedBefore
as the comparison
between elements.
Note: This method implements the mathematical notion of lexicographical
ordering, which has no connection to Unicode. If you are sorting strings
to present to the end-user, you should use String
APIs that perform
localized comparison.
Requires: isOrderedBefore
is a
strict weak ordering
over the elements of self
and other
.
Declaration
func lexicographicalCompare<OtherSequence : SequenceType where OtherSequence.Generator.Element == Generator.Element>(other: OtherSequence, @noescape isOrderedBefore: (C.Generator.Element, C.Generator.Element) throws -> Bool) rethrows -> Bool
Declared In
SequenceType
Returns an Array
containing the results of mapping transform
over self
.
Complexity: O(N).
Declaration
func map<T>(@noescape transform: (C.Generator.Element) throws -> T) rethrows -> [T]
Declared In
SequenceType
Returns the maximum element in self
or nil
if the sequence is empty.
Complexity: O(elements.count
).
Requires: isOrderedBefore
is a
strict weak ordering
over self
.
Declaration
func maxElement(@noescape isOrderedBefore: (C.Generator.Element, C.Generator.Element) throws -> Bool) rethrows -> C.Generator.Element?
Declared In
SequenceType
Returns the minimum element in self
or nil
if the sequence is empty.
Complexity: O(elements.count
).
Requires: isOrderedBefore
is a
strict weak ordering
over self
.
Declaration
func minElement(@noescape isOrderedBefore: (C.Generator.Element, C.Generator.Element) throws -> Bool) rethrows -> C.Generator.Element?
Declared In
SequenceType
Advance to the next element and return it, or nil
if no next
element exists.
Requires: No preceding call to self.next()
has returned nil
.
Declaration
mutating func next() -> C.Generator.Element?
Returns a subsequence, up to maxLength
in length, containing the
initial elements.
If maxLength
exceeds self.count
, the result contains all
the elements of self
.
Requires: maxLength >= 0
Declaration
func prefix(maxLength: Int) -> AnySequence<C.Generator.Element>
Declared In
SequenceType
Returns the result of repeatedly calling combine
with an
accumulated value initialized to initial
and each element of
self
, in turn, i.e. return
combine(combine(...combine(combine(initial, self[0]),
self[1]),...self[count-2]), self[count-1])
.
Declaration
func reduce<T>(initial: T, @noescape combine: (T, C.Generator.Element) throws -> T) rethrows -> T
Declared In
SequenceType
Returns an Array
containing the elements of self
in reverse
order.
Complexity: O(N), where N is the length of self
.
Declaration
func reverse() -> [C.Generator.Element]
Declared In
SequenceType
Returns an Array
containing the sorted elements of source
according to isOrderedBefore
.
The sorting algorithm is not stable (can change the relative order of
elements for which isOrderedBefore
does not establish an order).
Requires: isOrderedBefore
is a
strict weak ordering
over the elements in self
.
Declaration
func sort(@noescape isOrderedBefore: (C.Generator.Element, C.Generator.Element) -> Bool) -> [C.Generator.Element]
Declared In
SequenceType
Returns the maximal SubSequence
s of self
, in order, that
don't contain elements satisfying the predicate isSeparator
.
maxSplit
: The maximum number of SubSequence
s to
return, minus 1.
If maxSplit + 1
SubSequence
s are returned, the last one is
a suffix of self
containing the remaining elements.
The default value is Int.max
.
allowEmptySubsequences
: If true
, an empty SubSequence
is produced in the result for each pair of consecutive elements
satisfying isSeparator
.
The default value is false
.
Requires: maxSplit >= 0
Declaration
func split(maxSplit: Int = default, allowEmptySlices: Bool = default, @noescape isSeparator: (C.Generator.Element) throws -> Bool) rethrows -> [AnySequence<C.Generator.Element>]
Declared In
SequenceType
Returns true
iff self
begins with elements equivalent to those of
other
, using isEquivalent
as the equivalence test. Returns true
if
other
is empty.
Requires: isEquivalent
is an
equivalence relation.
Declaration
func startsWith<OtherSequence : SequenceType where OtherSequence.Generator.Element == Generator.Element>(other: OtherSequence, @noescape isEquivalent: (C.Generator.Element, C.Generator.Element) throws -> Bool) rethrows -> Bool
Declared In
SequenceType
Returns a slice, up to maxLength
in length, containing the
final elements of s
.
If maxLength
exceeds s.count
, the result contains all
the elements of s
.
Requires: self
is a finite sequence.
Requires: maxLength >= 0
Declaration
func suffix(maxLength: Int) -> AnySequence<C.Generator.Element>
Declared In
SequenceType
Returns a value less than or equal to the number of elements in
self
, nondestructively.
Complexity: O(N).
Declaration
func underestimateCount() -> Int
Declared In
SequenceType
Conditionally Inherited Items
The initializers, methods, and properties listed below may be available on this type under certain conditions (such as methods that are available on Array
when its elements are Equatable
) or may not ever be available if that determination is beyond SwiftDoc.org's capabilities. Please open an issue on GitHub if you see something out of place!
Where Generator == Self, Self : GeneratorType
Returns a generator over the elements of this sequence.
Complexity: O(1).
Declaration
func generate() -> PermutationGenerator<C, Indices>
Declared In
SequenceType
Where Generator.Element : Comparable
Returns true
iff self
precedes other
in a lexicographical
("dictionary") ordering, using "<" as the comparison between elements.
Note: This method implements the mathematical notion of lexicographical
ordering, which has no connection to Unicode. If you are sorting strings
to present to the end-user, you should use String
APIs that perform
localized comparison.
Declaration
func lexicographicalCompare<OtherSequence : SequenceType where OtherSequence.Generator.Element == Generator.Element>(other: OtherSequence) -> Bool
Declared In
SequenceType
Returns the maximum element in self
or nil
if the sequence is empty.
Complexity: O(elements.count
).
Declaration
func maxElement() -> C.Generator.Element?
Declared In
SequenceType
Returns the minimum element in self
or nil
if the sequence is empty.
Complexity: O(elements.count
).
Declaration
func minElement() -> C.Generator.Element?
Declared In
SequenceType
Returns an Array
containing the sorted elements of source
.
The sorting algorithm is not stable (can change the relative order of elements that compare equal).
Requires: The less-than operator (func <
) defined in
the Comparable
conformance is a
strict weak ordering
over the elements in self
.
Declaration
func sort() -> [C.Generator.Element]
Declared In
SequenceType
Where Generator.Element : Equatable
Returns true
iff element
is in self
.
Declaration
func contains(element: C.Generator.Element) -> Bool
Declared In
SequenceType
Returns true
iff self
and other
contain the same elements in the
same order.
Declaration
func elementsEqual<OtherSequence : SequenceType where OtherSequence.Generator.Element == Generator.Element>(other: OtherSequence) -> Bool
Declared In
SequenceType
Returns the maximal SubSequence
s of self
, in order, around elements
equatable to separator
.
maxSplit
: The maximum number of SubSequence
s to
return, minus 1.
If maxSplit + 1
SubSequence
s are returned, the last one is
a suffix of self
containing the remaining elements.
The default value is Int.max
.
allowEmptySubsequences
: If true
, an empty SubSequence
is produced in the result for each pair of consecutive elements
satisfying isSeparator
.
The default value is false
.
Requires: maxSplit >= 0
Declaration
func split(separator: C.Generator.Element, maxSplit: Int = default, allowEmptySlices: Bool = default) -> [AnySequence<C.Generator.Element>]
Declared In
SequenceType
Returns true
iff the initial elements of self
are equal to prefix
.
Returns true
if other
is empty.
Declaration
func startsWith<OtherSequence : SequenceType where OtherSequence.Generator.Element == Generator.Element>(other: OtherSequence) -> Bool
Declared In
SequenceType
Where Generator.Element : SequenceType
A concatenation of the elements of self
.
Declaration
func flatten() -> FlattenSequence<PermutationGenerator<C, Indices>>
Declared In
SequenceType
Returns a view, whose elements are the result of interposing a given
separator
between the elements of the sequence self
.
For example,
[[1, 2, 3], [4, 5, 6], [7, 8, 9]].joinWithSeparator([-1, -2])
yields [1, 2, 3, -1, -2, 4, 5, 6, -1, -2, 7, 8, 9]
.
Declaration
func joinWithSeparator<Separator : SequenceType where Separator.Generator.Element == Generator.Element.Generator.Element>(separator: Separator) -> JoinSequence<PermutationGenerator<C, Indices>>
Declared In
SequenceType
Where Generator.Element == String
Interpose the separator
between elements of self
, then concatenate
the result. For example:
["foo", "bar", "baz"].joinWithSeparator("-|-") // "foo-|-bar-|-baz"
Declaration
func joinWithSeparator(separator: String) -> String
Declared In
SequenceType
A generator that adapts a collection
C
and any sequence of itsIndex
type to present the collection's elements in a permuted order.Deprecated: PermitationGenerator will be removed in Swift 3.