scala.collection.mutable.WrappedArray
The class of the iterator returned by the iterator
method.
The type implementing this traversable
The type implementing this traversable
A class supporting filtered operations.
Test two objects for inequality.
Test two objects for inequality.
true
if !(this == that), false otherwise.
Equivalent to x.hashCode
except for boxed numeric types and null
.
Equivalent to x.hashCode
except for boxed numeric types and null
.
For numerics, it returns a hash value which is consistent
with value equality: if two value type instances compare
as true, then ## will produce the same hash value for each
of them.
For null
returns a hashcode where null.hashCode
throws a
NullPointerException
.
a hash value consistent with ==
[use case]
the element type of the returned collection.
the traversable to append.
a new wrapped array which contains all elements of this wrapped array
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 wrapped array followed by all elements of that
.
[use case]
the element type of the returned collection.
the traversable to append.
a new wrapped array which contains all elements of this wrapped array
followed by all elements of that
.
[use case]
the prepended element
a new wrapped array consisting of elem
followed
by all elements of this wrapped array.
Applies a binary operator to a start value and all elements of this wrapped array, going left to right.
Applies a binary operator to a start value and all elements of this wrapped array, 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
the result type of the binary operator.
the start value.
the binary operator.
the result of inserting op
between consecutive elements of this wrapped array,
going left to right with the start value z
on the left:
op(...op(op(z, x1), x2), ..., xn)
where x_{1}, ..., x_{n}
are the elements of this wrapped array.
A syntactic sugar for out of order folding.
A syntactic sugar for out of order folding. See fold
.
Example:
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
[use case]
the appended element
a new wrapped array consisting of
all elements of this wrapped array followed by elem
.
@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)
Applies a binary operator to all elements of this wrapped array and a start value, going right to left.
Applies a binary operator to all elements of this wrapped array and a start value, going right to left.
Note: :\
is alternate syntax for foldRight
; xs :\ z
is the same as
xs foldRight 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 = (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 wrapped array,
going right to left with the start value z
on the right:
op(x1, op(x2, ... op(xn, z)...))
where x_{1}, ..., x_{n}
are the elements of this wrapped array.
Test two objects for equality.
Test two objects for equality.
The expression x == that
is equivalent to if (x eq null) that eq null else x.equals(that)
.
true
if the receiver object is equivalent to the argument; false
otherwise.
Appends all elements of this wrapped array to a string builder.
Appends all elements of this wrapped array to a string builder.
The written text consists of the string representations (w.r.t. the method
toString
) of all elements of this wrapped array 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 wrapped array to a string builder using a separator string.
Appends all elements of this wrapped array 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 wrapped array, 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 wrapped array to a string builder using start, end, and separator strings.
Appends all elements of this wrapped array 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 wrapped array 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)
an operator used to accumulate results within a partition
an associative operator used to combine results from different partitions
Composes this partial function with a transformation function that gets applied to results of this partial function.
Composes this partial function with a transformation function that gets applied to results of this partial function.
the result type of the transformation function.
the transformation function
a partial function with the same domain as this partial function, which maps
arguments x
to k(this(x))
.
The element at given index
The element at given index
the element of this wrapped array at index idx
, where 0
indicates the first element.
The underlying array
The underlying array
Cast the receiver object to be of type T0
.
Cast the receiver object to be of type T0
.
Note that the success of a cast at runtime is modulo Scala's erasure semantics.
Therefore the expression 1.asInstanceOf[String]
will throw a ClassCastException
at
runtime, while the expression List(1).asInstanceOf[List[String]]
will not.
In the latter example, because the type argument is erased as part of compilation it is
not possible to check whether the contents of the list are of the requested type.
the receiver object.
if the receiver object is not an instance of the erasure of type T0
.
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 wrapped array should be compared
true
, if this wrapped array can possibly equal that
, false
otherwise. The test
takes into consideration only the run-time types of objects but ignores their elements.
Clones this object, including the underlying Array.
Clones this object, including the underlying Array.
a copy of the receiver object.
[use case]
the element type of the returned collection.
the partial function which filters and maps the wrapped array.
a new wrapped array 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 wrapped array for which the given partial function is defined, and applies the partial function to it.
Finds the first element of the wrapped array for which the given partial function is defined, and applies the partial function to it.
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 wrapped array.
"abbbc".combinations(2) = Iterator(ab, ac, bb, bc)
The factory companion object that builds instances of class WrappedArray.
The factory companion object that builds instances of class WrappedArray.
(or its Iterable
superclass where class WrappedArray is not a Seq
.)
Composes two instances of Function1 in a new Function1, with this function applied last.
Composes two instances of Function1 in a new Function1, with this function applied last.
the type to which function g
can be applied
a function A => T1
a new function f
such that f(x) == apply(g(x))
Tests whether this wrapped array contains a given value as an element.
Tests whether this wrapped array contains a given value as an element.
the element to test.
true
if this wrapped array has an element that is
is equal (wrt ==
) to elem
, false
otherwise.
Tests whether this wrapped array contains a given sequence as a slice.
Tests whether this wrapped array contains a given sequence as a slice.
the sequence to test
true
if this wrapped array contains a slice with the same elements
as that
, otherwise false
.
[use case]
the array to fill.
the starting index.
the maximal number of elements to copy.
[use case]
the array to fill.
[use case]
the array to fill.
the starting index.
Copies all elements of this wrapped array to a buffer.
Copies all elements of this wrapped array to a buffer.
The buffer to which elements are copied.
Tests whether every element of this wrapped array relates to the corresponding element of another sequence by satisfying a test predicate.
Tests whether every element of this wrapped array 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 wrapped array
and y
of that
, otherwise false
.
Counts the number of elements in the wrapped array which satisfy a predicate.
Counts the number of elements in the wrapped array which satisfy a predicate.
the predicate used to test elements.
the number of elements satisfying the predicate p
.
Creates a possible nested IndexedSeq
which consists of all the elements
of this array.
Creates a possible nested IndexedSeq
which consists of all the elements
of this array. If the elements are arrays themselves, the deep
transformation
is applied recursively to them. The stringPrefix
of the IndexedSeq
is
"Array", hence the IndexedSeq
prints like an array with all its
elements shown, and the same recursively for any subarrays.
Example:
Array(Array(1, 2), Array(3, 4)).deep.toString
prints: Array(Array(1, 2), Array(3, 4))
An possibly nested indexed sequence of consisting of all the elements of the array.
[use case]
the sequence of elements to remove
a new wrapped array which contains all elements of this wrapped array
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 wrapped array from this wrapped array without any duplicate elements.
Builds a new wrapped array from this wrapped array without any duplicate elements.
A new wrapped array which contains the first occurrence of every element of this wrapped array.
Selects all elements except first n ones.
Selects all elements except first n ones.
the number of elements to drop from this wrapped array.
a wrapped array consisting of all elements of this wrapped array except the first n
ones, or else the
empty wrapped array, if this wrapped array 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 wrapped array consisting of all elements of this wrapped array except the last n
ones, or else the
empty wrapped array, if this wrapped array has less than n
elements.
Drops longest prefix of elements that satisfy a predicate.
Drops longest prefix of elements that satisfy a predicate.
The predicate used to test elements.
the longest suffix of this wrapped array whose first element
does not satisfy the predicate p
.
The manifest of the element type
The manifest of the element type
Tests whether this wrapped array ends with the given sequence.
Tests whether this wrapped array ends with the given sequence.
the sequence to test
true
if this wrapped array has that
as a suffix, false
otherwise.
Tests whether the argument (arg0
) is a reference to the receiver object (this
).
Tests whether the argument (arg0
) is a reference to the receiver object (this
).
The eq
method implements an equivalence relation on
non-null instances of AnyRef
, and has three additional properties:
x
and y
of type AnyRef
, multiple invocations of
x.eq(y)
consistently returns true
or consistently returns false
.x
of type AnyRef
, x.eq(null)
and null.eq(x)
returns false
.null.eq(null)
returns true
. When overriding the equals
or hashCode
methods, it is important to ensure that their behavior is
consistent with reference equality. Therefore, if two objects are references to each other (o1 eq o2
), they
should be equal to each other (o1 == o2
) and they should hash to the same value (o1.hashCode == o2.hashCode
).
true
if the argument is a reference to the receiver object; 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 wrapped array.
Tests whether a predicate holds for some of the elements of this wrapped array.
the predicate used to test elements.
true
if the given predicate p
holds for some of the
elements of this wrapped array, otherwise false
.
Selects all elements of this wrapped array which satisfy a predicate.
Selects all elements of this wrapped array which satisfy a predicate.
the predicate used to test elements.
a new wrapped array consisting of all elements of this wrapped array that satisfy the given
predicate p
. The order of the elements is preserved.
Selects all elements of this wrapped array which do not satisfy a predicate.
Selects all elements of this wrapped array which do not satisfy a predicate.
the predicate used to test elements.
a new wrapped array consisting of all elements of this wrapped array that do not satisfy the given
predicate p
. The order of the elements is preserved.
Called by the garbage collector on the receiver object when there are no more references to the object.
Called by the garbage collector on the receiver object when there are no more references to the object.
The details of when and if the finalize
method is invoked, as
well as the interaction between finalize
and non-local returns
and exceptions, are all platform dependent.
Finds the first element of the wrapped array satisfying a predicate, if any.
Finds the first element of the wrapped array satisfying a predicate, if any.
the predicate used to test elements.
an option value containing the first element in the wrapped array
that satisfies p
, or None
if none exists.
[use case]
the element type of the returned collection.
the function to apply to each element.
a new wrapped array resulting from applying the given collection-valued function
f
to each element of this wrapped array and concatenating the results.
Folds the elements of this wrapped array using the specified associative binary operator.
Folds the elements of this wrapped array 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 wrapped array, going left to right.
Applies a binary operator to a start value and all elements of this wrapped array, going left to right.
the result type of the binary operator.
the start value.
the binary operator.
the result of inserting op
between consecutive elements of this wrapped array,
going left to right with the start value z
on the left:
op(...op(z, x1), x2, ..., xn)
where x_{1}, ..., x_{n}
are the elements of this wrapped array.
Applies a binary operator to all elements of this wrapped array and a start value, going right to left.
Applies a binary operator to all elements of this wrapped array and a start value, going right to left.
the result type of the binary operator.
the start value.
the binary operator.
the result of inserting op
between consecutive elements of this wrapped array,
going right to left with the start value z
on the right:
op(x1, op(x2, ... op(xn, z)...))
where x_{1}, ..., x_{n}
are the elements of this wrapped array.
Tests whether a predicate holds for all elements of this wrapped array.
Tests whether a predicate holds for all elements of this wrapped array.
the predicate used to test elements.
true
if the given predicate p
holds for all elements
of this wrapped array, otherwise false
.
[use case]
the function that is applied for its side-effect to every element.
The result of function f
is discarded.
The generic builder that builds instances of WrappedArray at arbitrary element types.
The generic builder that builds instances of WrappedArray at arbitrary element types.
A representation that corresponds to the dynamic class of the receiver object.
A representation that corresponds to the dynamic class of the receiver object.
The nature of the representation is platform dependent.
a representation that corresponds to the dynamic class of the receiver object.
not specified by SLS as a member of AnyRef
Partitions this wrapped array into a map of wrapped arrays according to some discriminator function.
Partitions this wrapped array into a map of wrapped arrays 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 wrapped array.
the type of keys returned by the discriminator function.
the discriminator function.
A map from keys to wrapped arrays 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 wrapped array of those elements x
for which f(x)
equals k
.
Partitions elements in fixed size wrapped arrays.
Partitions elements in fixed size wrapped arrays.
the number of elements per group
An iterator producing wrapped arrays of size size
, except the
last will be truncated if the elements don't divide evenly.
Iterator#grouped
Tests whether this wrapped array is known to have a finite size.
Tests whether this wrapped array 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 WrappedArray produce a value from the hashcodes of all the elements of the wrapped array.
Hashcodes for WrappedArray produce a value from the hashcodes of all the elements of the wrapped array.
the hash code value for this object.
Selects the first element of this wrapped array.
Selects the first element of this wrapped array.
the first element of this wrapped array.
if the wrapped array is empty.
Optionally selects the first element.
Optionally selects the first element.
the first element of this wrapped array if it is nonempty,
None
if it is empty.
[use case]
the element value to search for.
the start index
the index >= from
of the first element of this wrapped array that is equal (wrt ==
)
to elem
, or -1
, if none exists.
[use case]
the element value to search for.
the index of the first element of this wrapped array that is equal (wrt ==
)
to elem
, or -1
, if none exists.
Finds first index after or at a start index where this wrapped array contains a given sequence as a slice.
Finds first index after or at a start index where this wrapped array contains a given sequence as a slice.
the sequence to test
the start index
the first index >= from
such that the elements of this wrapped array starting at this index
match the elements of sequence that
, or -1
of no such subsequence exists.
Finds first index where this wrapped array contains a given sequence as a slice.
Finds first index where this wrapped array contains a given sequence as a slice.
the sequence to test
the first index such that the elements of this wrapped array 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.
the predicate used to test elements.
the start index
the index >= from
of the first element of this wrapped array 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.
the predicate used to test elements.
the index of the first element of this wrapped array 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 wrapped array.
Selects all elements except the last.
Selects all elements except the last.
a wrapped array consisting of all elements of this wrapped array except the last one.
if the wrapped array is empty.
Iterates over the inits of this wrapped array.
Iterates over the inits of this wrapped array. The first value will be this
wrapped array and the final one will be an empty wrapped array, with the intervening
values the results of successive applications of init
.
an iterator over all the inits of this wrapped array
List(1,2,3).inits = Iterator(List(1,2,3), List(1,2), List(1), Nil)
[use case]
the sequence of elements to intersect with.
a new wrapped array which contains all elements of this wrapped array
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 wrapped array contains given index.
Tests whether this wrapped array 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 wrapped array contains an element at position idx
, false
otherwise.
Tests whether the wrapped array is empty.
Tests whether the wrapped array is empty.
true
if the wrapped array contains no elements, false
otherwise.
Test whether the dynamic type of the receiver object is T0
.
Test whether the dynamic type of the receiver object is T0
.
Note that the result of the test is modulo Scala's erasure semantics.
Therefore the expression 1.isInstanceOf[String]
will return false
, while the
expression List(1).isInstanceOf[List[String]]
will return true
.
In the latter example, because the type argument is erased as part of compilation it is
not possible to check whether the contents of the list are of the specified type.
true
if the receiver object is an instance of erasure of type T0
; false
otherwise.
Tests whether this wrapped array can be repeatedly traversed.
Tests whether this wrapped array 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 wrapped array.
If the wrapped array is empty.
[use case]
the element value to search for.
the end index.
the index <= end
of the last element of this wrapped array that is equal (wrt ==
)
to elem
, or -1
, if none exists.
[use case]
the element value to search for.
the index of the last element of this wrapped array that is equal (wrt ==
)
to elem
, or -1
, if none exists.
Finds last index before or at a given end index where this wrapped array contains a given sequence as a slice.
Finds last index before or at a given end index where this wrapped array contains a given sequence as a slice.
the sequence to test
the end index
the last index <= end
such that the elements of this wrapped array starting at this index
match the elements of sequence that
, or -1
of no such subsequence exists.
Finds last index where this wrapped array contains a given sequence as a slice.
Finds last index where this wrapped array contains a given sequence as a slice.
the sequence to test
the last index such that the elements of this wrapped array 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 wrapped array 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.
the predicate used to test elements.
the index of the last element of this wrapped array 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 wrapped array$ if it is nonempty,
None
if it is empty.
The length of the array
The length of the array
the number of elements in this wrapped array.
Compares the length of this wrapped array to a test value.
Compares the length of this wrapped array 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.
Turns this partial function into an plain function returning an Option
result.
Turns this partial function into an plain function returning an Option
result.
a function that takes an argument x
to Some(this(x))
if this
is defined for x
, and to None
otherwise.
Function.unlift
[use case]
the element type of the returned collection.
the function to apply to each element.
a new wrapped array resulting from applying the given function
f
to each element of this wrapped array and collecting the results.
[use case]
the largest element of this wrapped array.
[use case]
the smallest element of this wrapped array
Displays all elements of this wrapped array in a string.
Displays all elements of this wrapped array in a string.
a string representation of this wrapped array. In the resulting string
the string representations (w.r.t. the method toString
)
of all elements of this wrapped array follow each other without any
separator string.
Displays all elements of this wrapped array in a string using a separator string.
Displays all elements of this wrapped array in a string using a separator string.
the separator string.
a string representation of this wrapped array. In the resulting string
the string representations (w.r.t. the method toString
)
of all elements of this wrapped array are separated by the string sep
.
List(1, 2, 3).mkString("|") = "1|2|3"
Displays all elements of this wrapped array in a string using start, end, and separator strings.
Displays all elements of this wrapped array in a string using start, end, and separator strings.
the starting string.
the separator string.
the ending string.
a string representation of this wrapped array. 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 wrapped array are separated by
the string sep
.
List(1, 2, 3).mkString("(", "; ", ")") = "(1; 2; 3)"
Equivalent to !(this eq that)
.
Equivalent to !(this eq that)
.
true
if the argument is not a reference to the receiver object; false
otherwise.
Creates new builder for this collection ==> move to subclasses
Creates new builder for this collection ==> move to subclasses
Tests whether the wrapped array is not empty.
Tests whether the wrapped array is not empty.
true
if the wrapped array contains at least one element, false
otherwise.
Wakes up a single thread that is waiting on the receiver object's monitor.
Wakes up a single thread that is waiting on the receiver object's monitor.
not specified by SLS as a member of AnyRef
Wakes up all threads that are waiting on the receiver object's monitor.
Wakes up all threads that are waiting on the receiver object's monitor.
not specified by SLS as a member of AnyRef
Composes this partial function with a fallback partial function which gets applied where this partial function is not defined.
Composes this partial function with a fallback partial function which gets applied where this partial function is not defined.
the argument type of the fallback function
the result type of the fallback function
the fallback function
a partial function which has as domain the union of the domains
of this partial function and that
. The resulting partial function
takes x
to this(x)
where this
is defined, and to that(x)
where it is not.
[use case]
the target length
the padding value
a new wrapped array consisting of
all elements of this wrapped array followed by the minimal number of occurrences of elem
so
that the resulting wrapped array 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 wrapped array in two wrapped arrays according to a predicate.
Partitions this wrapped array in two wrapped arrays according to a predicate.
the predicate on which to partition.
a pair of wrapped arrays: the first wrapped array consists of all elements that
satisfy the predicate p
and the second wrapped array consists of all elements
that don't. The relative order of the elements in the resulting wrapped arrays
is the same as in the original wrapped array.
[use case]
the index of the first replaced element
the number of elements to drop in the original wrapped array
a new wrapped array consisting of all elements of this wrapped array
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 wrapped array.
"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.
the predicate used to test elements.
the length of the longest prefix of this wrapped array
such that every element of the segment satisfies the predicate p
.
[use case]
the product of all elements in this wrapped array 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 wrapped array and as result type of product
.
Examples of such types are: Long
, Float
, Double
, BigInt
.
Reduces the elements of this wrapped array using the specified associative binary operator.
Reduces the elements of this wrapped array 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 wrapped array is nonempty.
if this wrapped array is empty.
Optionally applies a binary operator to all elements of this wrapped array, going left to right.
Optionally applies a binary operator to all elements of this wrapped array, going left to right.
the result type of the binary operator.
the binary operator.
an option value containing the result of reduceLeft(op)
is this wrapped array is nonempty,
None
otherwise.
Reduces the elements of this wrapped array, if any, using the specified associative binary operator.
Reduces the elements of this wrapped array, 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 wrapped array, going right to left.
Applies a binary operator to all elements of this wrapped array, going right to left.
the result type of the binary operator.
the binary operator.
the result of inserting op
between consecutive elements of this wrapped array,
going right to left:
op(x,,1,,, op(x,,2,,, ..., op(x,,n-1,,, x,,n,,)...))
where x_{1}, ..., x_{n}
are the elements of this wrapped array.
if this wrapped array is empty.
Optionally applies a binary operator to all elements of this wrapped array, going right to left.
Optionally applies a binary operator to all elements of this wrapped array, going right to left.
the result type of the binary operator.
the binary operator.
an option value containing the result of reduceRight(op)
is this wrapped array is nonempty,
None
otherwise.
The collection of type wrapped array underlying this TraversableLike
object.
The collection of type wrapped array underlying this TraversableLike
object.
By default this is implemented as the TraversableLike
object itself,
but this can be overridden.
Returns new wrapped array wih elements in reversed order.
Returns new wrapped array wih elements in reversed order.
A new wrapped array with all elements of this wrapped array in reversed order.
An iterator yielding elements in reversed order.
An iterator yielding elements in reversed order.
Note: xs.reverseIterator
is the same as xs.reverse.iterator
but might be more efficient.
an iterator yielding the elements of this wrapped array in reversed order
[use case] Note: xs.reverseMap(f)
is the same as xs.reverse.map(f)
but might be more efficient.
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 wrapped array resulting from applying the given function
f
to each element of this wrapped array and collecting the results in reversed order.
[use case]
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 wrapped array containing the prefix scan of the elements in this wrapped array
Produces a collection containing cummulative results of applying the operator going left to right.
Produces a collection containing cummulative results of applying the operator going left to right.
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 cummulative results of applying the operator going right to left.
Produces a collection containing cummulative results of applying the operator going right to left. The head of the collection is the last cummulative result.
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.
the predicate used to test elements.
the index where the search starts.
the length of the longest segment of this wrapped array starting from index from
such that every element of the segment satisfies the predicate p
.
A version of this collection with all of the operations implemented sequentially (i.
A version of this collection with all of the operations implemented sequentially (i.e. in a single-threaded manner).
This method returns a reference to this collection. In parallel collections, it is redefined to return a sequential implementation of this collection. In both cases, it has O(1) complexity.
a sequential view of the collection.
The size of this wrapped array, equivalent to length
.
The size of this wrapped array, equivalent to length
.
the number of elements in this wrapped array.
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
the lowest index to include from this wrapped array.
the highest index to EXCLUDE from this wrapped array.
a wrapped array containing the elements greater than or equal to
index from
extending up to (but not including) index until
of this wrapped array.
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 wrapped arrays of size size
, except the
last and the only element will be truncated if there are
fewer elements than size.
Iterator#sliding
Sorts this WrappedArray according to the Ordering which results from transforming an implicitly given Ordering with a transformation function.
Sorts this WrappedArray 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 wrapped array consisting of the elements of this wrapped array
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)
scala.math.Ordering
Sorts this wrapped array according to a comparison function.
Sorts this wrapped array according to a comparison function.
The sort is stable. That is, elements that are equal wrt 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 wrapped array consisting of the elements of this wrapped array
sorted according to the comparison function lt
.
List("Steve", "Tom", "John", "Bob").sortWith(_.compareTo(_) < 0) = List("Bob", "John", "Steve", "Tom")
Sorts this wrapped array according to an Ordering.
Sorts this wrapped array according to an Ordering.
The sort is stable. That is, elements that are equal wrt lt
appear in the
same order in the sorted sequence as in the original.
the ordering to be used to compare elements.
a wrapped array consisting of the elements of this wrapped array
sorted according to the ordering ord
.
scala.math.Ordering
Splits this wrapped array into a prefix/suffix pair according to a predicate.
Splits this wrapped array 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.
the test predicate
a pair consisting of the longest prefix of this wrapped array whose
elements all satisfy p
, and the rest of this wrapped array.
Splits this wrapped array into two at a given position.
Splits this wrapped array 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 wrapped arrays consisting of the first n
elements of this wrapped array, and the other elements.
Tests whether this wrapped array contains the given sequence at a given index.
Tests whether this wrapped array 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 wrapped array at
index offset
, otherwise false
.
Tests whether this wrapped array starts with the given sequence.
Tests whether this wrapped array 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 wrapped array. By default the string prefix is the
simple name of the collection class wrapped array.
[use case]
the sum of all elements in this wrapped array 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 wrapped array 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 wrapped array consisting of all elements of this wrapped array except the first one.
if the wrapped array is empty.
Iterates over the tails of this wrapped array.
Iterates over the tails of this wrapped array. The first value will be this
wrapped array and the final one will be an empty wrapped array, with the intervening
values the results of successive applications of tail
.
an iterator over all the tails of this wrapped array
List(1,2,3).tails = Iterator(List(1,2,3), List(2,3), List(3), Nil)
Selects first n elements.
Selects first n elements.
Tt number of elements to take from this wrapped array.
a wrapped array consisting only of the first n
elements of this wrapped array,
or else the whole wrapped array, if it has less than n
elements.
Selects last n elements.
Selects last n elements.
the number of elements to take
a wrapped array consisting only of the last n
elements of this wrapped array, or else the
whole wrapped array, 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 predicate used to test elements.
the longest prefix of this wrapped array whose elements all satisfy
the predicate p
.
The underlying collection seen as an instance of WrappedArray
.
The underlying collection seen as an instance of WrappedArray
.
By default this is implemented as the current collection object itself,
but this can be overridden.
[use case]
an array containing all elements of this wrapped array.
A ClassManifest
must be available for the element type of this wrapped array.
Overridden for efficiency
Overridden for efficiency
a buffer containing all elements of this wrapped array.
A conversion from collections of type Repr
to WrappedArray
objects.
A conversion from collections of type Repr
to WrappedArray
objects.
By default this is implemented as just a cast, but this can be overridden.
Converts this wrapped array to an indexed sequence.
Converts this wrapped array to an indexed sequence.
an indexed sequence containing all elements of this wrapped array.
Converts this wrapped array to an iterable collection.
Converts this wrapped array 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).
an Iterable
containing all elements of this wrapped array.
Returns an Iterator over the elements in this wrapped array.
Returns an Iterator over the elements in this wrapped array. Will return the same Iterator if this instance is already an Iterator.
an Iterator containing all elements of this wrapped array.
Converts this wrapped array to a list.
Converts this wrapped array to a list.
a list containing all elements of this wrapped array.
[use case]
a map of type immutable.Map[T, U]
containing all key/value pairs of type (T, U)
of this wrapped array.
Converts this wrapped array to a sequence.
Converts this wrapped array to a sequence.
Overridden for efficiency.
a sequence containing all elements of this wrapped array.
Converts this wrapped array to a set.
Converts this wrapped array to a set.
a set containing all elements of this wrapped array.
Converts this wrapped array to a stream.
Converts this wrapped array to a stream.
a stream containing all elements of this wrapped array.
Converts this wrapped array to a string.
Converts this wrapped array to a string.
a string representation of this collection. By default this
string consists of the stringPrefix
of this wrapped array, followed
by all elements separated by commas and enclosed in parentheses.
Converts this wrapped array to an unspecified Traversable.
Converts this wrapped array to an unspecified Traversable. Will return the same collection if this instance is already Traversable.
a Traversable containing all elements of this wrapped array.
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]
the sequence to add.
a new wrapped array which contains all elements of this wrapped array
followed by all elements of that
.
Converts this wrapped array of pairs into two collections of the first and second half of each pair.
Converts this wrapped array of pairs into two collections of the first and second half of each pair.
an implicit conversion which asserts that the element type of this wrapped array is a pair.
a pair wrapped arrays, containing the first, respectively second half of each element pair of this wrapped array.
Converts this wrapped array of triples into three collections of the first, second, and third element of each triple.
Converts this wrapped array of triples into three collections of the first, second, and third element of each triple.
an implicit conversion which asserts that the element type of this wrapped array is a triple.
a triple wrapped arrays, containing the first, second, respectively third member of each element triple of this wrapped array.
Update element at given index
Update element at given index
the new value.
[use case]
the position of the replacement
the replacing element
a copy of this wrapped array with the element at position index
replaced by elem
.
A sub-sequence view starting at index from
and extending up to (but not including) index until
.
A sub-sequence view starting at index from
and extending up to (but not including) index until
.
The index of the first element of the slice
The index of the element following the slice
a non-strict view of a slice of this wrapped array, starting at index from
and extending up to (but not including) index until
[email protected] The difference between view
and slice
is that view
produces
a view of the current sequence, whereas slice
produces a new sequence.
view(from, to) is equivalent to view.slice(from, to)
Creates a view of this iterable @see Iterable.
Creates a view of this iterable @see Iterable.View
a non-strict view of this wrapped array.
Creates a non-strict filter of this wrapped array.
Creates a non-strict filter of this wrapped array.
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 wrapped array
which satisfy the predicate p
.
[use case]
the type of the second half of the returned pairs
The iterable providing the second half of each result pair
a new wrapped array containing pairs consisting of
corresponding elements of this wrapped array and that
. The length
of the returned collection is the minimum of the lengths of this wrapped array and that
.
[use case]
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 wrapped array is shorter than that
.
the element to be used to fill up the result if that
is shorter than this wrapped array.
a new wrapped array containing pairs consisting of
corresponding elements of this wrapped array and that
. The length
of the returned collection is the maximum of the lengths of this wrapped array and that
.
If this wrapped array is shorter than that
, thisElem
values are used to pad the result.
If that
is shorter than this wrapped array, thatElem
values are used to pad the result.
[use case]
A new wrapped array containing pairs consisting of all elements of this
wrapped array paired with their index. Indices start at 0
.
@example
List("a", "b", "c").zipWithIndex = List(("a", 0), ("b", 1), ("c", 2))