struct
LazyMapSequence
<
Base
:
SequenceType
,
Element
>
Inheritance |
LazySequenceType, SequenceType
View Protocol Hierarchy →
|
---|---|
Associated Types |
Type alias inferred.
Type alias inferred. |
Import |
|
Initializers
Create an instance with elements transform(x)
for each element
x
of base.
Deprecated: it will be removed in Swift 3, use '.lazy.map' on the sequence.
Declaration
init
(
_
base
:
Base
,
transform
: (
Base
.
Generator
.
Element
) -
>
Element
)
Instance Variables
Identical to self
.
Declaration
var
lazy
:
LazyMapSequence
<
Base
,
Element
>
{
get
}
Declared In
LazySequenceType
1 inherited item hidden. (Show all)
Instance Methods
Returns a subsequence containing all but the first element.
Complexity: O(1)
Declaration
func
dropFirst
() -
>
LazyMapSequence
<
Base
,
Element
>
.
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
<
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
() -
>
LazyMapSequence
<
Base
,
Element
>
.
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
<
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
: (
Generator
.
Element
,
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() {
(
"\(
n
): '\(
c
)'"
)
}
0
: '
S
'
1
: '
w
'
2
: '
i
'
3
: '
f
'
4
: '
t
'
Declaration
func
enumerate
() -
>
EnumerateSequence
<
LazyMapSequence
<
Base
,
Element
>
>
Declared In
SequenceType
Returns the elements of self
that satisfy predicate
.
Note: The elements of the result are computed on-demand, as
the result is used. No buffering storage is allocated and each
traversal step invokes predicate
on one or more underlying
elements.
Declaration
func
filter
(
predicate
: (
Generator
.
Elements
.
Generator
.
Element
) -
>
Bool
) -
>
LazyFilterSequence
<
Generator
.
Elements
>
Declared In
LazySequenceType
, 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
: (
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
: (
Generator
.
Element
)
throws
-
>
S
)
rethrows
-
>
[
S
.
Generator
.
Element
]
Declared In
SequenceType
Returns the concatenated results of mapping transform
over
self
. Equivalent to
self
.
map
(
transform
).
flatten
()
Complexity: O(1)
Declaration
func
flatMap
<
Intermediate
:
SequenceType
>
(
transform
: (
Generator
.
Elements
.
Generator
.
Element
) -
>
Intermediate
) -
>
LazySequence
<
FlattenSequence
<
LazyMapSequence
<
Generator
.
Elements
,
Intermediate
>
>
>
Declared In
LazySequenceType
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
: (
Generator
.
Element
)
throws
-
>
Void
)
rethrows
Declared In
SequenceType
Returns a generator over the elements of this sequence.
Complexity: O(1).
Declaration
func
generate
() -
>
LazyMapGenerator
<
Base
.
Generator
,
Element
>
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
: (
Generator
.
Element
,
Generator
.
Element
)
throws
-
>
Bool
)
rethrows
-
>
Bool
Declared In
SequenceType
Returns a LazyMapSequence
over this Sequence
. The elements of
the result are computed lazily, each time they are read, by
calling transform
function on a base element.
Declaration
func
map
<
U
>
(
transform
: (
Generator
.
Elements
.
Generator
.
Element
) -
>
U
) -
>
LazyMapSequence
<
Generator
.
Elements
,
U
>
Declared In
LazySequenceType
, 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
: (
Generator
.
Element
,
Generator
.
Element
)
throws
-
>
Bool
)
rethrows
-
>
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
: (
Generator
.
Element
,
Generator
.
Element
)
throws
-
>
Bool
)
rethrows
-
>
Generator
.
Element
?
Declared In
SequenceType
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
<
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
,
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
() -
>
[
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
: (
Generator
.
Element
,
Generator
.
Element
) -
>
Bool
) -
>
[
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
: (
Generator
.
Element
)
throws
-
>
Bool
)
rethrows
-
>
[
AnySequence
<
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
: (
Generator
.
Element
,
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
<
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
LazyMapSequence
, SequenceType
23 inherited items hidden. (Show all)
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 Elements == Self
Identical to self
.
Declaration
var
elements
:
LazyMapSequence
<
Base
,
Element
>
{
get
}
Declared In
LazySequenceType
1 inherited item hidden. (Show all)
Where Elements.Generator.Element == Generator.Element, Generator.Element : SequenceType
A concatenation of the elements of self
.
Declaration
func
flatten
() -
>
LazySequence
<
FlattenSequence
<
Generator
.
Elements
>
>
Declared In
LazySequenceType
1 inherited item hidden. (Show all)
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
() -
>
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
() -
>
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
() -
>
[
Generator
.
Element
]
Declared In
SequenceType
4 inherited items hidden. (Show all)
Where Generator.Element : Equatable
Returns true
iff element
is in self
.
Declaration
func
contains
(
element
:
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
:
Generator
.
Element
,
maxSplit
:
Int
=
default
,
allowEmptySlices
:
Bool
=
default
) -
>
[
AnySequence
<
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
4 inherited items hidden. (Show all)
Where Generator.Element : SequenceType
A concatenation of the elements of self
.
Declaration
func
flatten
() -
>
FlattenSequence
<
LazyMapSequence
<
Base
,
Element
>
>
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
<
LazyMapSequence
<
Base
,
Element
>
>
Declared In
SequenceType
2 inherited items hidden. (Show all)
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
Declared In
SequenceType
1 inherited item hidden. (Show all)
A
SequenceType
whose elements consist of those in aBase
SequenceType
passed through a transform function returningElement
. These elements are computed lazily, each time they're read, by calling the transform function on a base element.