The type implementing this traversable
The type implementing this traversable
A class supporting filtered operations.
Creates a new builder for this collection type.
Creates a new builder for this collection type.
[use case] Returns a new double linked list containing the elements from the left hand operand followed by the elements from the right hand operand.
Returns a new double linked list containing the elements from the left hand operand followed by the elements from the right hand operand. The element type of the double linked list is the most specific superclass encompassing the element types of the two operands.
Example:
scala> val a = LinkedList(1) a: scala.collection.mutable.LinkedList[Int] = LinkedList(1) scala> val b = LinkedList(2) b: scala.collection.mutable.LinkedList[Int] = LinkedList(2) scala> val c = a ++ b c: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2) scala> val d = LinkedList('a') d: scala.collection.mutable.LinkedList[Char] = LinkedList(a) scala> val e = c ++ d e: scala.collection.mutable.LinkedList[AnyVal] = LinkedList(1, 2, a)
the element type of the returned collection.
the traversable to append.
a new double linked list which contains all elements of this double linked list
followed by all elements of that
.
As with ++
, returns a new collection containing the elements from the
left operand followed by the elements from the right operand.
As with ++
, returns a new collection containing the elements from the
left operand followed by the elements from the right operand.
It differs from ++
in that the right operand determines the type of
the resulting collection rather than the left one.
Mnemonic: the COLon is on the side of the new COLlection type.
Example:
scala> val x = List(1) x: List[Int] = List(1) scala> val y = LinkedList(2) y: scala.collection.mutable.LinkedList[Int] = LinkedList(2) scala> val z = x ++: y z: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2)
This overload exists because: for the implementation of ++:
we should
reuse that of ++
because many collections override it with more
efficient versions.
Since TraversableOnce
has no ++
method, we have to implement that
directly, but Traversable
and down can use the overload.
the element type of the returned collection.
the class of the returned collection. Where possible, That
is
the same class as the current collection class Repr
, but this
depends on the element type B
being admissible for that class,
which means that an implicit instance of type CanBuildFrom[Repr, B, That]
is found.
the traversable to append.
an implicit value of class CanBuildFrom
which determines the
result class That
from the current representation type Repr
and the new element type B
.
a new collection of type That
which contains all elements
of this double linked list followed by all elements of that
.
[use case] As with ++
, returns a new collection containing the elements from the left operand followed by the
elements from the right operand.
As with ++
, returns a new collection containing the elements from the left operand followed by the
elements from the right operand.
It differs from ++
in that the right operand determines the type of
the resulting collection rather than the left one.
Mnemonic: the COLon is on the side of the new COLlection type.
Example:
scala> val x = List(1) x: List[Int] = List(1) scala> val y = LinkedList(2) y: scala.collection.mutable.LinkedList[Int] = LinkedList(2) scala> val z = x ++: y z: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2)
the element type of the returned collection.
the traversable to append.
a new double linked list which contains all elements of this double linked list
followed by all elements of that
.
[use case] A copy of the double linked list with an element prepended.
A copy of the double linked list with an element prepended.
Note that :-ending operators are right associative (see example).
A mnemonic for +:
vs. :+
is: the COLon goes on the COLlection side.
Also, the original double linked list is not modified, so you will want to capture the result.
Example:
scala> val x = LinkedList(1) x: scala.collection.mutable.LinkedList[Int] = LinkedList(1) scala> val y = 2 +: x y: scala.collection.mutable.LinkedList[Int] = LinkedList(2, 1) scala> println(x) LinkedList(1)
the prepended element
a new double linked list consisting of elem
followed
by all elements of this double linked list.
Applies a binary operator to a start value and all elements of this double linked list, going left to right.
Applies a binary operator to a start value and all elements of this double linked list, going left to right.
Note: /:
is alternate syntax for foldLeft
; z /: xs
is the same as
xs foldLeft z
.
Examples:
Note that the folding function used to compute b is equivalent to that used to compute c.
scala> val a = LinkedList(1,2,3,4) a: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 3, 4) scala> val b = (5 /: a)(_+_) b: Int = 15 scala> val c = (5 /: a)((x,y) => x + y) c: Int = 15
Note: will not terminate for infinite-sized collections.
the result type of the binary operator.
the start value.
the binary operator.
the result of inserting op
between consecutive elements of this double linked list,
going left to right with the start value z
on the left:
op(...op(op(z, x_1), x_2), ..., x_n)
where x1, ..., xn
are the elements of this double linked list.
[use case] A copy of this double linked list with an element appended.
A copy of this double linked list with an element appended.
A mnemonic for +:
vs. :+
is: the COLon goes on the COLlection side.
Note: will not terminate for infinite-sized collections.
Example:
scala> import scala.collection.mutable.LinkedList import scala.collection.mutable.LinkedList scala> val a = LinkedList(1) a: scala.collection.mutable.LinkedList[Int] = LinkedList(1) scala> val b = a :+ 2 b: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2) scala> println(a) LinkedList(1)
the appended element
a new double linked list consisting of
all elements of this double linked list followed by elem
.
Applies a binary operator to all elements of this double linked list and a start value, going right to left.
Applies a binary operator to all elements of this double linked list and a start value, going right to left.
Note: :\
is alternate syntax for foldRight
; xs :\ z
is the same as
xs foldRight z
.
Note: will not terminate for infinite-sized collections.
Examples:
Note that the folding function used to compute b is equivalent to that used to compute c.
scala> val a = LinkedList(1,2,3,4) a: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 3, 4) scala> val b = (a :\ 5)(_+_) b: Int = 15 scala> val c = (a :\ 5)((x,y) => x + y) c: Int = 15
the result type of the binary operator.
the start value
the binary operator
the result of inserting op
between consecutive elements of this double linked list,
going right to left with the start value z
on the right:
op(x_1, op(x_2, ... op(x_n, z)...))
where x1, ..., xn
are the elements of this double linked list.
Appends all elements of this double linked list to a string builder.
Appends all elements of this double linked list to a string builder.
The written text consists of the string representations (w.r.t. the method
toString
) of all elements of this double linked list without any separator string.
Example:
scala> val a = LinkedList(1,2,3,4) a: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 3, 4) scala> val b = new StringBuilder() b: StringBuilder = scala> val h = a.addString(b) b: StringBuilder = 1234
the string builder to which elements are appended.
the string builder b
to which elements were appended.
Appends all elements of this double linked list to a string builder using a separator string.
Appends all elements of this double linked list to a string builder using a separator string.
The written text consists of the string representations (w.r.t. the method toString
)
of all elements of this double linked list, separated by the string sep
.
Example:
scala> val a = LinkedList(1,2,3,4) a: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 3, 4) scala> val b = new StringBuilder() b: StringBuilder = scala> a.addString(b, ", ") res0: StringBuilder = 1, 2, 3, 4
the string builder to which elements are appended.
the separator string.
the string builder b
to which elements were appended.
Appends all elements of this double linked list to a string builder using start, end, and separator strings.
Appends all elements of this double linked list to a string builder using start, end, and separator strings.
The written text begins with the string start
and ends with the string end
.
Inside, the string representations (w.r.t. the method toString
)
of all elements of this double linked list are separated by the string sep
.
Example:
scala> val a = LinkedList(1,2,3,4) a: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 3, 4) scala> val b = new StringBuilder() b: StringBuilder = scala> a.addString(b, "LinkedList(", ", ", ")") res1: StringBuilder = LinkedList(1, 2, 3, 4)
the string builder to which elements are appended.
the starting string.
the separator string.
the ending string.
the string builder b
to which elements were appended.
Aggregates the results of applying an operator to subsequent elements.
Aggregates the results of applying an operator to subsequent elements.
This is a more general form of fold
and reduce
. It has similar
semantics, but does not require the result to be a supertype of the
element type. It traverses the elements in different partitions
sequentially, using seqop
to update the result, and then applies
combop
to results from different partitions. The implementation of
this operation may operate on an arbitrary number of collection
partitions, so combop
may be invoked an arbitrary number of times.
For example, one might want to process some elements and then produce
a Set
. In this case, seqop
would process an element and append it
to the list, while combop
would concatenate two lists from different
partitions together. The initial value z
would be an empty set.
pc.aggregate(Set[Int]())(_ += process(_), _ ++ _)
Another example is calculating geometric mean from a collection of doubles (one would typically require big doubles for this).
the type of accumulated results
the initial value for the accumulated result of the partition - this
will typically be the neutral element for the seqop
operator (e.g.
Nil
for list concatenation or 0
for summation) and may be evaluated
more than once
an operator used to accumulate results within a partition
an associative operator used to combine results from different partitions
If this
is empty then it does nothing and returns that
.
If this
is empty then it does nothing and returns that
. Otherwise, appends that
to this
. The append
requires a full traversal of this
.
Examples:
scala> val a = LinkedList(1, 2) a: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2) scala> val b = LinkedList(1, 2) b: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2) scala> a.append(b) res0: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 1, 2) scala> println(a) LinkedList(1, 2, 1, 2)
scala> val a = new LinkedList[Int]() a: scala.collection.mutable.LinkedList[Int] = LinkedList() scala> val b = LinkedList(1, 2) b: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2) scala> val c = a.append(b) c: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2) scala> println(a) LinkedList()
the list after append (this is the list itself if nonempty,
or list that
if list this is empty. )
Selects an element by its index in the double linked list.
Selects an element by its index in the double linked list.
Example:
scala> val x = LinkedList(1, 2, 3, 4, 5) x: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 3, 4, 5) scala> x(3) res1: Int = 4
the element of this double linked list at index idx
, where 0
indicates the first element.
if idx
does not satisfy 0 <= idx < length
.
Method called from equality methods, so that user-defined subclasses can refuse to be equal to other collections of the same kind.
Method called from equality methods, so that user-defined subclasses can refuse to be equal to other collections of the same kind.
The object with which this double linked list should be compared
true
, if this double linked list can possibly equal that
, false
otherwise. The test
takes into consideration only the run-time types of objects but ignores their elements.
Return a clone of this list.
Return a clone of this list.
a LinkedList
with the same elements.
[use case] Builds a new collection by applying a partial function to all elements of this double linked list on which the function is defined.
Builds a new collection by applying a partial function to all elements of this double linked list on which the function is defined.
the element type of the returned collection.
the partial function which filters and maps the double linked list.
a new double linked list resulting from applying the given partial function
pf
to each element on which it is defined and collecting the results.
The order of the elements is preserved.
Finds the first element of the double linked list for which the given partial function is defined, and applies the partial function to it.
Finds the first element of the double linked list for which the given partial function is defined, and applies the partial function to it.
Note: may not terminate for infinite-sized collections.
the partial function
an option value containing pf applied to the first
value for which it is defined, or None
if none exists.
Seq("a", 1, 5L).collectFirst({ case x: Int => x*10 }) = Some(10)
Iterates over combinations.
Iterates over combinations.
An Iterator which traverses the possible n-element combinations of this double linked list.
"abbbc".combinations(2) = Iterator(ab, ac, bb, bc)
Tests whether this double linked list contains a given value as an element.
Tests whether this double linked list contains a given value as an element.
Note: may not terminate for infinite-sized collections.
the element to test.
true
if this double linked list has an element that is equal (as
determined by ==
) to elem
, false
otherwise.
Tests whether this double linked list contains a given sequence as a slice.
Tests whether this double linked list contains a given sequence as a slice.
Note: may not terminate for infinite-sized collections.
the sequence to test
true
if this double linked list contains a slice with the same elements
as that
, otherwise false
.
[use case] Copies elements of this double linked list to an array.
Copies elements of this double linked list to an array.
Fills the given array xs
with at most len
elements of
this double linked list, starting at position start
.
Copying will stop once either the end of the current double linked list is reached,
or the end of the array is reached, or len
elements have been copied.
Note: will not terminate for infinite-sized collections.
the array to fill.
the starting index.
the maximal number of elements to copy.
[use case] Copies values of this double linked list to an array.
Copies values of this double linked list to an array.
Fills the given array xs
with values of this double linked list.
Copying will stop once either the end of the current double linked list is reached,
or the end of the array is reached.
Note: will not terminate for infinite-sized collections.
the array to fill.
[use case] Copies values of this double linked list to an array.
Copies values of this double linked list to an array.
Fills the given array xs
with values of this double linked list, beginning at index start
.
Copying will stop once either the end of the current double linked list is reached,
or the end of the array is reached.
Note: will not terminate for infinite-sized collections.
the array to fill.
the starting index.
Copies all elements of this double linked list to a buffer.
Copies all elements of this double linked list to a buffer.
Note: will not terminate for infinite-sized collections.
The buffer to which elements are copied.
Tests whether every element of this double linked list relates to the corresponding element of another sequence by satisfying a test predicate.
Tests whether every element of this double linked list relates to the corresponding element of another sequence by satisfying a test predicate.
the type of the elements of that
the other sequence
the test predicate, which relates elements from both sequences
true
if both sequences have the same length and
p(x, y)
is true
for all corresponding elements x
of this double linked list
and y
of that
, otherwise false
.
Counts the number of elements in the double linked list which satisfy a predicate.
Counts the number of elements in the double linked list which satisfy a predicate.
the predicate used to test elements.
the number of elements satisfying the predicate p
.
[use case] Computes the multiset difference between this double linked list and another sequence.
Computes the multiset difference between this double linked list and another sequence.
Note: will not terminate for infinite-sized collections.
the sequence of elements to remove
a new double linked list which contains all elements of this double linked list
except some of occurrences of elements that also appear in that
.
If an element value x
appears
n times in that
, then the first n occurrences of x
will not form
part of the result, but any following occurrences will.
Builds a new double linked list from this double linked list without any duplicate elements.
Builds a new double linked list from this double linked list without any duplicate elements.
Note: will not terminate for infinite-sized collections.
A new double linked list which contains the first occurrence of every element of this double linked list.
Selects all elements except first n ones.
Selects all elements except first n ones.
the number of elements to drop from this double linked list.
a double linked list consisting of all elements of this double linked list except the first n
ones, or else the
empty double linked list, if this double linked list has less than n
elements.
Selects all elements except last n ones.
Selects all elements except last n ones.
The number of elements to take
a double linked list consisting of all elements of this double linked list except the last n
ones, or else the
empty double linked list, if this double linked list has less than n
elements.
Drops longest prefix of elements that satisfy a predicate.
Drops longest prefix of elements that satisfy a predicate.
the longest suffix of this double linked list whose first element
does not satisfy the predicate p
.
Tests whether this double linked list ends with the given sequence.
Tests whether this double linked list ends with the given sequence.
Note: will not terminate for infinite-sized collections.
the sequence to test
true
if this double linked list has that
as a suffix, false
otherwise.
The equals method for arbitrary sequences.
The equals method for arbitrary sequences. Compares this sequence to some other object.
The object to compare the sequence to
true
if that
is a sequence that has the same elements as
this sequence in the same order, false
otherwise
Tests whether a predicate holds for some of the elements of this double linked list.
Tests whether a predicate holds for some of the elements of this double linked list.
Note: may not terminate for infinite-sized collections.
the predicate used to test elements.
true
if the given predicate p
holds for some of the
elements of this double linked list, otherwise false
.
Selects all elements of this double linked list which satisfy a predicate.
Selects all elements of this double linked list which satisfy a predicate.
the predicate used to test elements.
a new double linked list consisting of all elements of this double linked list that satisfy the given
predicate p
. The order of the elements is preserved.
Selects all elements of this double linked list which do not satisfy a predicate.
Selects all elements of this double linked list which do not satisfy a predicate.
the predicate used to test elements.
a new double linked list consisting of all elements of this double linked list that do not satisfy the given
predicate p
. The order of the elements is preserved.
Finds the first element of the double linked list satisfying a predicate, if any.
Finds the first element of the double linked list satisfying a predicate, if any.
Note: may not terminate for infinite-sized collections.
the predicate used to test elements.
an option value containing the first element in the double linked list
that satisfies p
, or None
if none exists.
[use case] Builds a new collection by applying a function to all elements of this double linked list and using the elements of the resulting collections.
Builds a new collection by applying a function to all elements of this double linked list and using the elements of the resulting collections.
For example:
def getWords(lines: Seq[String]): Seq[String] = lines flatMap (line => line split "\\W+")
The type of the resulting collection is guided by the static type of double linked list. This might cause unexpected results sometimes. For example:
// lettersOf will return a Seq[Char] of likely repeated letters, instead of a Set def lettersOf(words: Seq[String]) = words flatMap (word => word.toSet) // lettersOf will return a Set[Char], not a Seq def lettersOf(words: Seq[String]) = words.toSet flatMap (word => word.toSeq) // xs will be an Iterable[Int] val xs = Map("a" -> List(11,111), "b" -> List(22,222)).flatMap(_._2) // ys will be a Map[Int, Int] val ys = Map("a" -> List(1 -> 11,1 -> 111), "b" -> List(2 -> 22,2 -> 222)).flatMap(_._2)
the element type of the returned collection.
the function to apply to each element.
a new double linked list resulting from applying the given collection-valued function
f
to each element of this double linked list and concatenating the results.
Folds the elements of this double linked list using the specified associative binary operator.
Folds the elements of this double linked list using the specified associative binary operator.
The order in which operations are performed on elements is unspecified and may be nondeterministic.
a type parameter for the binary operator, a supertype of A
.
a neutral element for the fold operation; may be added to the result
an arbitrary number of times, and must not change the result (e.g., Nil
for list concatenation,
0 for addition, or 1 for multiplication.)
a binary operator that must be associative
the result of applying fold operator op
between all the elements and z
Applies a binary operator to a start value and all elements of this double linked list, going left to right.
Applies a binary operator to a start value and all elements of this double linked list, going left to right.
Note: will not terminate for infinite-sized collections.
the result type of the binary operator.
the start value.
the binary operator.
the result of inserting op
between consecutive elements of this double linked list,
going left to right with the start value z
on the left:
op(...op(z, x_1), x_2, ..., x_n)
where x1, ..., xn
are the elements of this double linked list.
Applies a binary operator to all elements of this double linked list and a start value, going right to left.
Applies a binary operator to all elements of this double linked list and a start value, going right to left.
Note: will not terminate for infinite-sized collections.
the result type of the binary operator.
the start value.
the binary operator.
the result of inserting op
between consecutive elements of this double linked list,
going right to left with the start value z
on the right:
op(x_1, op(x_2, ... op(x_n, z)...))
where x1, ..., xn
are the elements of this double linked list.
Tests whether a predicate holds for all elements of this double linked list.
Tests whether a predicate holds for all elements of this double linked list.
Note: may not terminate for infinite-sized collections.
the predicate used to test elements.
true
if the given predicate p
holds for all elements
of this double linked list, otherwise false
.
[use case] Applies a function f
to all elements of this double linked list.
Applies a function f
to all elements of this double linked list.
Note: this method underlies the implementation of most other bulk operations. Subclasses should re-implement this method if a more efficient implementation exists.
the function that is applied for its side-effect to every element.
The result of function f
is discarded.
Returns string formatted according to given format
string.
Returns string formatted according to given format
string.
Format strings are as for String.format
(@see java.lang.String.format).
Partitions this double linked list into a map of double linked lists according to some discriminator function.
Partitions this double linked list into a map of double linked lists according to some discriminator function.
Note: this method is not re-implemented by views. This means when applied to a view it will always force the view and return a new double linked list.
the type of keys returned by the discriminator function.
the discriminator function.
A map from keys to double linked lists such that the following invariant holds:
(xs partition f)(k) = xs filter (x => f(x) == k)
That is, every key k
is bound to a double linked list of those elements x
for which f(x)
equals k
.
Partitions elements in fixed size double linked lists.
Partitions elements in fixed size double linked lists.
the number of elements per group
An iterator producing double linked lists of size size
, except the
last will be truncated if the elements don't divide evenly.
scala.collection.Iterator, method grouped
Tests whether this double linked list is known to have a finite size.
Tests whether this double linked list is known to have a finite size.
All strict collections are known to have finite size. For a non-strict
collection such as Stream
, the predicate returns true
if all
elements have been computed. It returns false
if the stream is
not yet evaluated to the end.
Note: many collection methods will not work on collections of infinite sizes.
true
if this collection is known to have finite size,
false
otherwise.
Hashcodes for DoubleLinkedList
produce a value from the hashcodes of all the
elements of the double linked list.
Hashcodes for DoubleLinkedList
produce a value from the hashcodes of all the
elements of the double linked list.
Selects the first element of this double linked list.
Selects the first element of this double linked list.
the first element of this double linked list.
if the double linked list is empty.
Optionally selects the first element.
Optionally selects the first element.
the first element of this double linked list if it is nonempty,
None
if it is empty.
[use case] Finds index of first occurrence of some value in this double linked list after or at some start index.
Finds index of first occurrence of some value in this double linked list after or at some start index.
Note: may not terminate for infinite-sized collections.
the element value to search for.
the start index
the index >= from
of the first element of this double linked list that is equal (as determined by ==
)
to elem
, or -1
, if none exists.
[use case] Finds index of first occurrence of some value in this double linked list.
Finds index of first occurrence of some value in this double linked list.
Note: may not terminate for infinite-sized collections.
the element value to search for.
the index of the first element of this double linked list that is equal (as determined by ==
)
to elem
, or -1
, if none exists.
Finds first index after or at a start index where this double linked list contains a given sequence as a slice.
Finds first index after or at a start index where this double linked list contains a given sequence as a slice.
Note: may not terminate for infinite-sized collections.
the sequence to test
the start index
the first index >= from
such that the elements of this double linked list starting at this index
match the elements of sequence that
, or -1
of no such subsequence exists.
Finds first index where this double linked list contains a given sequence as a slice.
Finds first index where this double linked list contains a given sequence as a slice.
Note: may not terminate for infinite-sized collections.
the sequence to test
the first index such that the elements of this double linked list starting at this index
match the elements of sequence that
, or -1
of no such subsequence exists.
Finds index of the first element satisfying some predicate after or at some start index.
Finds index of the first element satisfying some predicate after or at some start index.
Note: may not terminate for infinite-sized collections.
the predicate used to test elements.
the start index
the index >= from
of the first element of this double linked list that satisfies the predicate p
,
or -1
, if none exists.
Finds index of first element satisfying some predicate.
Finds index of first element satisfying some predicate.
Note: may not terminate for infinite-sized collections.
the predicate used to test elements.
the index of the first element of this double linked list that satisfies the predicate p
,
or -1
, if none exists.
Produces the range of all indices of this sequence.
Produces the range of all indices of this sequence.
a Range
value from 0
to one less than the length of this double linked list.
Selects all elements except the last.
Selects all elements except the last.
a double linked list consisting of all elements of this double linked list except the last one.
if the double linked list is empty.
Iterates over the inits of this double linked list.
Iterates over the inits of this double linked list. The first value will be this
double linked list and the final one will be an empty double linked list, with the intervening
values the results of successive applications of init
.
an iterator over all the inits of this double linked list
List(1,2,3).inits = Iterator(List(1,2,3), List(1,2), List(1), Nil)
Insert linked list that
at current position of this linked list
Insert linked list that
at current position of this linked list
this linked list must not be empty
[use case] Computes the multiset intersection between this double linked list and another sequence.
Computes the multiset intersection between this double linked list and another sequence.
Note: may not terminate for infinite-sized collections.
the sequence of elements to intersect with.
a new double linked list which contains all elements of this double linked list
which also appear in that
.
If an element value x
appears
n times in that
, then the first n occurrences of x
will be retained
in the result, but any following occurrences will be omitted.
Tests whether this double linked list contains given index.
Tests whether this double linked list contains given index.
The implementations of methods apply
and isDefinedAt
turn a Seq[A]
into
a PartialFunction[Int, A]
.
the index to test
true
if this double linked list contains an element at position idx
, false
otherwise.
Tests whether this double linked list is empty.
Tests whether this double linked list is empty.
true
if the double linked list contain no elements, false
otherwise.
Tests whether this double linked list can be repeatedly traversed.
Tests whether this double linked list can be repeatedly traversed.
true
Creates a new iterator over all elements contained in this iterable object.
Creates a new iterator over all elements contained in this iterable object.
the new iterator
Selects the last element.
Selects the last element.
The last element of this double linked list.
If the double linked list is empty.
[use case] Finds index of last occurrence of some value in this double linked list before or at a given end index.
Finds index of last occurrence of some value in this double linked list before or at a given end index.
the element value to search for.
the end index.
the index <= end
of the last element of this double linked list that is equal (as determined by ==
)
to elem
, or -1
, if none exists.
[use case] Finds index of last occurrence of some value in this double linked list.
Finds index of last occurrence of some value in this double linked list.
Note: will not terminate for infinite-sized collections.
the element value to search for.
the index of the last element of this double linked list that is equal (as determined by ==
)
to elem
, or -1
, if none exists.
Finds last index before or at a given end index where this double linked list contains a given sequence as a slice.
Finds last index before or at a given end index where this double linked list contains a given sequence as a slice.
the sequence to test
the end index
the last index <= end
such that the elements of this double linked list starting at this index
match the elements of sequence that
, or -1
of no such subsequence exists.
Finds last index where this double linked list contains a given sequence as a slice.
Finds last index where this double linked list contains a given sequence as a slice.
Note: will not terminate for infinite-sized collections.
the sequence to test
the last index such that the elements of this double linked list starting a this index
match the elements of sequence that
, or -1
of no such subsequence exists.
Finds index of last element satisfying some predicate before or at given end index.
Finds index of last element satisfying some predicate before or at given end index.
the predicate used to test elements.
the index <= end
of the last element of this double linked list that satisfies the predicate p
,
or -1
, if none exists.
Finds index of last element satisfying some predicate.
Finds index of last element satisfying some predicate.
Note: will not terminate for infinite-sized collections.
the predicate used to test elements.
the index of the last element of this double linked list that satisfies the predicate p
,
or -1
, if none exists.
Optionally selects the last element.
Optionally selects the last element.
the last element of this double linked list$ if it is nonempty,
None
if it is empty.
Determines the length of this double linked list by traversing and counting every node.
Determines the length of this double linked list by traversing and counting every node.
the number of elements in this double linked list.
Compares the length of this double linked list to a test value.
Compares the length of this double linked list to a test value.
the test value that gets compared with the length.
A value x
where
x < 0 if this.length < len x == 0 if this.length == len x > 0 if this.length > len
The method as implemented here does not call length
directly; its running time
is O(length min len)
instead of O(length)
. The method should be overwritten
if computing length
is cheap.
[use case] Builds a new collection by applying a function to all elements of this double linked list.
Builds a new collection by applying a function to all elements of this double linked list.
the element type of the returned collection.
the function to apply to each element.
a new double linked list resulting from applying the given function
f
to each element of this double linked list and collecting the results.
[use case] Finds the largest element.
Finds the largest element.
the largest element of this double linked list.
[use case] Finds the smallest element.
Finds the smallest element.
the smallest element of this double linked list
Displays all elements of this double linked list in a string.
Displays all elements of this double linked list in a string.
a string representation of this double linked list. In the resulting string
the string representations (w.r.t. the method toString
)
of all elements of this double linked list follow each other without any
separator string.
Displays all elements of this double linked list in a string using a separator string.
Displays all elements of this double linked list in a string using a separator string.
the separator string.
a string representation of this double linked list. In the resulting string
the string representations (w.r.t. the method toString
)
of all elements of this double linked list are separated by the string sep
.
List(1, 2, 3).mkString("|") = "1|2|3"
Displays all elements of this double linked list in a string using start, end, and separator strings.
Displays all elements of this double linked list in a string using start, end, and separator strings.
the starting string.
the separator string.
the ending string.
a string representation of this double linked list. The resulting string
begins with the string start
and ends with the string
end
. Inside, the string representations (w.r.t. the method
toString
) of all elements of this double linked list are separated by
the string sep
.
List(1, 2, 3).mkString("(", "; ", ")") = "(1; 2; 3)"
Tests whether the double linked list is not empty.
Tests whether the double linked list is not empty.
true
if the double linked list contains at least one element, false
otherwise.
[use case] A copy of this double linked list with an element value appended until a given target length is reached.
A copy of this double linked list with an element value appended until a given target length is reached.
the target length
the padding value
a new double linked list consisting of
all elements of this double linked list followed by the minimal number of occurrences of elem
so
that the resulting double linked list has a length of at least len
.
Returns a parallel implementation of this collection.
Returns a parallel implementation of this collection.
For most collection types, this method creates a new parallel collection by copying
all the elements. For these collection, par
takes linear time. Mutable collections
in this category do not produce a mutable parallel collection that has the same
underlying dataset, so changes in one collection will not be reflected in the other one.
Specific collections (e.g. ParArray
or mutable.ParHashMap
) override this default
behaviour by creating a parallel collection which shares the same underlying dataset.
For these collections, par
takes constant or sublinear time.
All parallel collections return a reference to themselves.
a parallel implementation of this collection
The default par
implementation uses the combiner provided by this method
to create a new parallel collection.
The default par
implementation uses the combiner provided by this method
to create a new parallel collection.
a combiner for the parallel collection of type ParRepr
Partitions this double linked list in two double linked lists according to a predicate.
Partitions this double linked list in two double linked lists according to a predicate.
the predicate on which to partition.
a pair of double linked lists: the first double linked list consists of all elements that
satisfy the predicate p
and the second double linked list consists of all elements
that don't. The relative order of the elements in the resulting double linked lists
is the same as in the original double linked list.
[use case] Produces a new double linked list where a slice of elements in this double linked list is replaced by another sequence.
Produces a new double linked list where a slice of elements in this double linked list is replaced by another sequence.
the index of the first replaced element
the number of elements to drop in the original double linked list
a new double linked list consisting of all elements of this double linked list
except that replaced
elements starting from from
are replaced
by patch
.
Iterates over distinct permutations.
Iterates over distinct permutations.
An Iterator which traverses the distinct permutations of this double linked list.
"abb".permutations = Iterator(abb, bab, bba)
Returns the length of the longest prefix whose elements all satisfy some predicate.
Returns the length of the longest prefix whose elements all satisfy some predicate.
Note: may not terminate for infinite-sized collections.
the predicate used to test elements.
the length of the longest prefix of this double linked list
such that every element of the segment satisfies the predicate p
.
A reference to the node in the linked list preceeding the current node.
[use case] Multiplies up the elements of this collection.
Multiplies up the elements of this collection.
the product of all elements in this double linked list of numbers of type Int
.
Instead of Int
, any other type T
with an implicit Numeric[T]
implementation
can be used as element type of the double linked list and as result type of product
.
Examples of such types are: Long
, Float
, Double
, BigInt
.
Reduces the elements of this double linked list using the specified associative binary operator.
Reduces the elements of this double linked list using the specified associative binary operator.
The order in which operations are performed on elements is unspecified and may be nondeterministic.
A type parameter for the binary operator, a supertype of A
.
A binary operator that must be associative.
The result of applying reduce operator op
between all the elements if the double linked list is nonempty.
if this double linked list is empty.
Applies a binary operator to all elements of this double linked list, going left to right.
Applies a binary operator to all elements of this double linked list, going left to right.
Note: will not terminate for infinite-sized collections.
the result type of the binary operator.
the binary operator.
the result of inserting op
between consecutive elements of this double linked list,
going left to right:
op( op( ... op(x_1, x_2) ..., x_{n-1}), x_n)
where x1, ..., xn
are the elements of this double linked list.
if this double linked list is empty.
Optionally applies a binary operator to all elements of this double linked list, going left to right.
Optionally applies a binary operator to all elements of this double linked list, going left to right.
Note: will not terminate for infinite-sized collections.
the result type of the binary operator.
the binary operator.
an option value containing the result of reduceLeft(op)
is this double linked list is nonempty,
None
otherwise.
Reduces the elements of this double linked list, if any, using the specified associative binary operator.
Reduces the elements of this double linked list, if any, using the specified associative binary operator.
The order in which operations are performed on elements is unspecified and may be nondeterministic.
A type parameter for the binary operator, a supertype of A
.
A binary operator that must be associative.
An option value containing result of applying reduce operator op
between all
the elements if the collection is nonempty, and None
otherwise.
Applies a binary operator to all elements of this double linked list, going right to left.
Applies a binary operator to all elements of this double linked list, going right to left.
Note: will not terminate for infinite-sized collections.
the result type of the binary operator.
the binary operator.
the result of inserting op
between consecutive elements of this double linked list,
going right to left:
op(x_1, op(x_2, ..., op(x_{n-1}, x_n)...))
where x1, ..., xn
are the elements of this double linked list.
if this double linked list is empty.
Optionally applies a binary operator to all elements of this double linked list, going right to left.
Optionally applies a binary operator to all elements of this double linked list, going right to left.
Note: will not terminate for infinite-sized collections.
the result type of the binary operator.
the binary operator.
an option value containing the result of reduceRight(op)
is this double linked list is nonempty,
None
otherwise.
Removes the current node from the double linked list.
Removes the current node from the double linked list. If the node was chained into a double linked list, it will no longer be a part of it. If the node was the last node in the list, i.e. a sentinel, this method does nothing.
Note: this method will not set the fields elem
, next
or prev
of the
current node, i.e. this
node itself will still point "into" the list it
was in.
(Changed in version 2.9.0) Double linked list now removes the current node from the list.
The collection of type double linked list underlying this TraversableLike
object.
The collection of type double linked list underlying this TraversableLike
object.
By default this is implemented as the TraversableLike
object itself,
but this can be overridden.
Returns new double linked list wih elements in reversed order.
Returns new double linked list wih elements in reversed order.
Note: will not terminate for infinite-sized collections.
A new double linked list with all elements of this double linked list in reversed order.
An iterator yielding elements in reversed order.
An iterator yielding elements in reversed order.
Note: will not terminate for infinite-sized collections.
Note: xs.reverseIterator
is the same as xs.reverse.iterator
but might be more efficient.
an iterator yielding the elements of this double linked list in reversed order
[use case] Builds a new collection by applying a function to all elements of this double linked list and collecting the results in reversed order.
Builds a new collection by applying a function to all elements of this double linked list and collecting the results in reversed order.
Note: will not terminate for infinite-sized collections.
Note: xs.reverseMap(f)
is the same as xs.reverse.map(f)
but might be more efficient.
the element type of the returned collection.
the function to apply to each element.
a new double linked list resulting from applying the given function
f
to each element of this double linked list and collecting the results in reversed order.
[use case] Checks if the other iterable collection contains the same elements in the same order as this double linked list.
Checks if the other iterable collection contains the same elements in the same order as this double linked list.
Note: will not terminate for infinite-sized collections.
the collection to compare with.
true
, if both collections contain the same elements in the same order, false
otherwise.
Computes a prefix scan of the elements of the collection.
Computes a prefix scan of the elements of the collection.
Note: The neutral element z
may be applied more than once.
element type of the resulting collection
type of the resulting collection
neutral element for the operator op
the associative operator for the scan
combiner factory which provides a combiner
a new double linked list containing the prefix scan of the elements in this double linked list
Produces a collection containing cumulative results of applying the operator going left to right.
Produces a collection containing cumulative results of applying the operator going left to right.
Note: will not terminate for infinite-sized collections.
the type of the elements in the resulting collection
the actual type of the resulting collection
the initial value
the binary operator applied to the intermediate result and the element
an implicit value of class CanBuildFrom
which determines the
result class That
from the current representation type Repr
and the new element type B
.
collection with intermediate results
Produces a collection containing cumulative results of applying the operator going right to left.
Produces a collection containing cumulative results of applying the operator going right to left. The head of the collection is the last cumulative result.
Note: will not terminate for infinite-sized collections.
Example:
List(1, 2, 3, 4).scanRight(0)(_ + _) == List(10, 9, 7, 4, 0)
the type of the elements in the resulting collection
the actual type of the resulting collection
the initial value
the binary operator applied to the intermediate result and the element
an implicit value of class CanBuildFrom
which determines the
result class That
from the current representation type Repr
and the new element type B
.
collection with intermediate results
(Changed in version 2.9.0) The behavior of scanRight
has changed. The previous behavior can be reproduced with scanRight.reverse.
Computes length of longest segment whose elements all satisfy some predicate.
Computes length of longest segment whose elements all satisfy some predicate.
Note: may not terminate for infinite-sized collections.
the predicate used to test elements.
the index where the search starts.
the length of the longest segment of this double linked list starting from index from
such that every element of the segment satisfies the predicate p
.
The size of this double linked list, equivalent to length
.
The size of this double linked list, equivalent to length
.
Note: will not terminate for infinite-sized collections.
the number of elements in this double linked list.
Selects an interval of elements.
Selects an interval of elements. The returned collection is made up
of all elements x
which satisfy the invariant:
from <= indexOf(x) < until
a double linked list containing the elements greater than or equal to
index from
extending up to (but not including) index until
of this double linked list.
Groups elements in fixed size blocks by passing a "sliding window" over them (as opposed to partitioning them, as is done in grouped.
Groups elements in fixed size blocks by passing a "sliding window" over them (as opposed to partitioning them, as is done in grouped.)
the number of elements per group
the distance between the first elements of successive groups (defaults to 1)
An iterator producing double linked lists of size size
, except the
last and the only element will be truncated if there are
fewer elements than size.
scala.collection.Iterator, method sliding
Groups elements in fixed size blocks by passing a "sliding window" over them (as opposed to partitioning them, as is done in grouped.
Groups elements in fixed size blocks by passing a "sliding window" over them (as opposed to partitioning them, as is done in grouped.)
the number of elements per group
An iterator producing double linked lists of size size
, except the
last and the only element will be truncated if there are
fewer elements than size.
scala.collection.Iterator, method sliding
Sorts this DoubleLinkedList
according to the Ordering which results from transforming
an implicitly given Ordering with a transformation function.
Sorts this DoubleLinkedList
according to the Ordering which results from transforming
an implicitly given Ordering with a transformation function.
the target type of the transformation f
, and the type where
the ordering ord
is defined.
the transformation function mapping elements
to some other domain B
.
the ordering assumed on domain B
.
a double linked list consisting of the elements of this double linked list
sorted according to the ordering where x < y
if
ord.lt(f(x), f(y))
.
val words = "The quick brown fox jumped over the lazy dog".split(' ') // this works because scala.Ordering will implicitly provide an Ordering[Tuple2[Int, Char]] words.sortBy(x => (x.length, x.head)) res0: Array[String] = Array(The, dog, fox, the, lazy, over, brown, quick, jumped)
Note: will not terminate for infinite-sized collections.
Sorts this double linked list according to a comparison function.
Sorts this double linked list according to a comparison function.
Note: will not terminate for infinite-sized collections.
The sort is stable. That is, elements that are equal (as determined by
lt
) appear in the same order in the sorted sequence as in the original.
the comparison function which tests whether its first argument precedes its second argument in the desired ordering.
a double linked list consisting of the elements of this double linked list
sorted according to the comparison function lt
.
List("Steve", "Tom", "John", "Bob").sortWith(_.compareTo(_) < 0) = List("Bob", "John", "Steve", "Tom")
Sorts this double linked list according to an Ordering.
Sorts this double linked list according to an Ordering.
The sort is stable. That is, elements that are equal (as determined by
lt
) appear in the same order in the sorted sequence as in the original.
the ordering to be used to compare elements.
a double linked list consisting of the elements of this double linked list
sorted according to the ordering ord
.
Splits this double linked list into a prefix/suffix pair according to a predicate.
Splits this double linked list into a prefix/suffix pair according to a predicate.
Note: c span p
is equivalent to (but possibly more efficient than)
(c takeWhile p, c dropWhile p)
, provided the evaluation of the
predicate p
does not cause any side-effects.
a pair consisting of the longest prefix of this double linked list whose
elements all satisfy p
, and the rest of this double linked list.
Splits this double linked list into two at a given position.
Splits this double linked list into two at a given position.
Note: c splitAt n
is equivalent to (but possibly more efficient than)
(c take n, c drop n)
.
the position at which to split.
a pair of double linked lists consisting of the first n
elements of this double linked list, and the other elements.
Tests whether this double linked list contains the given sequence at a given index.
Tests whether this double linked list contains the given sequence at a given index.
Note: If the both the receiver object this
and the argument
that
are infinite sequences this method may not terminate.
the sequence to test
the index where the sequence is searched.
true
if the sequence that
is contained in this double linked list at
index offset
, otherwise false
.
Tests whether this double linked list starts with the given sequence.
Tests whether this double linked list starts with the given sequence.
the sequence to test
true
if this collection has that
as a prefix, false
otherwise.
Defines the prefix of this object's toString
representation.
Defines the prefix of this object's toString
representation.
a string representation which starts the result of toString
applied to this double linked list. By default the string prefix is the
simple name of the collection class double linked list.
[use case] Sums up the elements of this collection.
Sums up the elements of this collection.
the sum of all elements in this double linked list of numbers of type Int
.
Instead of Int
, any other type T
with an implicit Numeric[T]
implementation
can be used as element type of the double linked list and as result type of sum
.
Examples of such types are: Long
, Float
, Double
, BigInt
.
Selects all elements except the first.
Selects all elements except the first.
a double linked list consisting of all elements of this double linked list except the first one.
if the double linked list is empty.
Iterates over the tails of this double linked list.
Iterates over the tails of this double linked list. The first value will be this
double linked list and the final one will be an empty double linked list, with the intervening
values the results of successive applications of tail
.
an iterator over all the tails of this double linked list
List(1,2,3).tails = Iterator(List(1,2,3), List(2,3), List(3), Nil)
Selects first n elements.
Selects first n elements.
the number of elements to take from this double linked list.
a double linked list consisting only of the first n
elements of this double linked list,
or else the whole double linked list, if it has less than n
elements.
Selects last n elements.
Selects last n elements.
the number of elements to take
a double linked list consisting only of the last n
elements of this double linked list, or else the
whole double linked list, if it has less than n
elements.
Takes longest prefix of elements that satisfy a predicate.
Takes longest prefix of elements that satisfy a predicate.
the longest prefix of this double linked list whose elements all satisfy
the predicate p
.
The underlying collection seen as an instance of
.DoubleLinkedList
The underlying collection seen as an instance of
.
By default this is implemented as the current collection object itself,
but this can be overridden.
DoubleLinkedList
[use case] Converts this double linked list into another by copying all elements.
Converts this double linked list into another by copying all elements.
Note: will not terminate for infinite-sized collections.
The collection type to build.
a new collection containing all elements of this double linked list.
[use case] Converts this double linked list to an array.
Converts this double linked list to an array.
Note: will not terminate for infinite-sized collections.
an array containing all elements of this double linked list.
An ClassTag
must be available for the element type of this double linked list.
Converts this double linked list to a mutable buffer.
Converts this double linked list to a mutable buffer.
Note: will not terminate for infinite-sized collections.
a buffer containing all elements of this double linked list.
A conversion from collections of type Repr
to
objects.DoubleLinkedList
A conversion from collections of type Repr
to
objects.
By default this is implemented as just a cast, but this can be overridden.
DoubleLinkedList
Converts this double linked list to an indexed sequence.
Converts this double linked list to an indexed sequence.
Note: will not terminate for infinite-sized collections.
an indexed sequence containing all elements of this double linked list.
Converts this double linked list to an iterable collection.
Converts this double linked list to an iterable collection. Note that
the choice of target Iterable
is lazy in this default implementation
as this TraversableOnce
may be lazy and unevaluated (i.e. it may
be an iterator which is only traversable once).
Note: will not terminate for infinite-sized collections.
an Iterable
containing all elements of this double linked list.
Returns an Iterator over the elements in this double linked list.
Returns an Iterator over the elements in this double linked list. Will return the same Iterator if this instance is already an Iterator.
Note: will not terminate for infinite-sized collections.
an Iterator containing all elements of this double linked list.
Converts this double linked list to a list.
Converts this double linked list to a list.
Note: will not terminate for infinite-sized collections.
a list containing all elements of this double linked list.
[use case] Converts this double linked list to a map.
Converts this double linked list to a map. This method is unavailable unless the elements are members of Tuple2, each ((T, U)) becoming a key-value pair in the map. Duplicate keys will be overwritten by later keys: if this is an unordered collection, which key is in the resulting map is undefined.
Note: will not terminate for infinite-sized collections.
a map of type immutable.Map[T, U]
containing all key/value pairs of type (T, U)
of this double linked list.
Converts this double linked list to a sequence.
Converts this double linked list to a sequence.
Note: will not terminate for infinite-sized collections.
Overridden for efficiency.
a sequence containing all elements of this double linked list.
Converts this double linked list to a set.
Converts this double linked list to a set.
Note: will not terminate for infinite-sized collections.
a set containing all elements of this double linked list.
Converts this double linked list to a stream.
Converts this double linked list to a stream.
Note: will not terminate for infinite-sized collections.
a stream containing all elements of this double linked list.
Converts this double linked list to a string.
Converts this double linked list to a string.
a string representation of this collection. By default this
string consists of the stringPrefix
of this double linked list, followed
by all elements separated by commas and enclosed in parentheses.
Converts this double linked list to an unspecified Traversable.
Converts this double linked list to an unspecified Traversable. Will return the same collection if this instance is already Traversable.
Note: will not terminate for infinite-sized collections.
a Traversable containing all elements of this double linked list.
Converts this double linked list to a Vector.
Converts this double linked list to a Vector.
Note: will not terminate for infinite-sized collections.
a vector containing all elements of this double linked list.
Applies a transformation function to all values contained in this sequence.
Applies a transformation function to all values contained in this sequence. The transformation function produces new values from existing elements.
the transformation to apply
the sequence itself.
[use case] Produces a new sequence which contains all elements of this double linked list and also all elements of a given sequence.
Produces a new sequence which contains all elements of this double linked list and also all elements of
a given sequence. xs union ys
is equivalent to xs ++ ys
.
Another way to express this
is that xs union ys
computes the order-presevring multi-set union of xs
and ys
.
union
is hence a counter-part of diff
and intersect
which also work on multi-sets.
Note: will not terminate for infinite-sized collections.
the sequence to add.
a new double linked list which contains all elements of this double linked list
followed by all elements of that
.
Replaces element at given index with a new value.
Replaces element at given index with a new value.
if the index is not valid.
[use case] A copy of this double linked list with one single replaced element.
A copy of this double linked list with one single replaced element.
the position of the replacement
the replacing element
a copy of this double linked list with the element at position index
replaced by elem
.
Creates a non-strict view of a slice of this double linked list.
Creates a non-strict view of a slice of this double linked list.
Note: the difference between view
and slice
is that view
produces
a view of the current double linked list, whereas slice
produces a new double linked list.
Note: view(from, to)
is equivalent to view.slice(from, to)
the index of the first element of the view
the index of the element following the view
a non-strict view of a slice of this double linked list, starting at index from
and extending up to (but not including) index until
.
Creates a non-strict view of this double linked list.
Creates a non-strict view of this double linked list.
a non-strict view of this double linked list.
Creates a non-strict filter of this double linked list.
Creates a non-strict filter of this double linked list.
Note: the difference between c filter p
and c withFilter p
is that
the former creates a new collection, whereas the latter only
restricts the domain of subsequent map
, flatMap
, foreach
,
and withFilter
operations.
the predicate used to test elements.
an object of class WithFilter
, which supports
map
, flatMap
, foreach
, and withFilter
operations.
All these operations apply to those elements of this double linked list
which satisfy the predicate p
.
[use case] Returns a double linked list formed from this double linked list and another iterable collection by combining corresponding elements in pairs.
Returns a double linked list formed from this double linked list and another iterable collection by combining corresponding elements in pairs. If one of the two collections is longer than the other, its remaining elements are ignored.
the type of the second half of the returned pairs
The iterable providing the second half of each result pair
a new double linked list containing pairs consisting of
corresponding elements of this double linked list and that
. The length
of the returned collection is the minimum of the lengths of this double linked list and that
.
[use case] Returns a double linked list formed from this double linked list and another iterable collection by combining corresponding elements in pairs.
Returns a double linked list formed from this double linked list and another iterable collection by combining corresponding elements in pairs. If one of the two collections is shorter than the other, placeholder elements are used to extend the shorter collection to the length of the longer.
the type of the second half of the returned pairs
The iterable providing the second half of each result pair
the element to be used to fill up the result if this double linked list is shorter than that
.
the element to be used to fill up the result if that
is shorter than this double linked list.
a new double linked list containing pairs consisting of
corresponding elements of this double linked list and that
. The length
of the returned collection is the maximum of the lengths of this double linked list and that
.
If this double linked list is shorter than that
, thisElem
values are used to pad the result.
If that
is shorter than this double linked list, thatElem
values are used to pad the result.
[use case] Zips this double linked list with its indices.
Zips this double linked list with its indices.
A new double linked list containing pairs consisting of all elements of this
double linked list paired with their index. Indices start at 0
.
List("a", "b", "c").zipWithIndex = List(("a", 0), ("b", 1), ("c", 2))
(doubleLinkedListLike: MonadOps[A]).filter(p)
(doubleLinkedListLike: MonadOps[A]).flatMap(f)
(doubleLinkedListLike: MonadOps[A]).map(f)
(doubleLinkedListLike: MonadOps[A]).withFilter(p)
This extensible class may be used as a basis for implementing double linked lists. Type variable
A
refers to the element type of the list, type variableThis
is used to model self types of linked lists.The invariant of this data structure is that
prev
is always a reference to the previous node in the list. Ifthis
is the first node of the list,prev
will benull
. Fieldnext
is set tothis
iff the list is empty.Examples (right arrow represents
next
, left arrow representsprev
,_
represents no value):type of the elements contained in the double linked list
the type of the actual linked list holding the elements
1.0, 08/07/2003
2.8