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] Returns a new $coll containing the elements from the left hand operand followed by the elements from the right hand operand.
Returns a new $coll containing the elements from the left hand operand followed by the elements from the right hand operand. The element type of the $coll 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 $coll which contains all elements of this $coll
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.
$thatinfo
the traversable to append.
$bfinfo
a new collection of type That which contains all elements
of this $coll 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 $coll which contains all elements of this $coll
followed by all elements of that.
Applies a binary operator to a start value and all elements of this $coll, going left to right.
Applies a binary operator to a start value and all elements of this $coll, 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
$willNotTerminateInf $orderDependentFold
the result type of the binary operator.
the start value.
the binary operator.
the result of inserting op between consecutive elements of this $coll,
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 $coll.
Applies a binary operator to all elements of this $coll and a start value, going right to left.
Applies a binary operator to all elements of this $coll and a start value, going right to left.
Note: :\ is alternate syntax for foldRight; xs :\ z is the same as
xs foldRight z.
$willNotTerminateInf
$orderDependentFold
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 $coll,
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 $coll.
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 $coll to a string builder.
Appends all elements of this $coll to a string builder.
The written text consists of the string representations (w.r.t. the method
toString) of all elements of this $coll 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 $coll to a string builder using a separator string.
Appends all elements of this $coll 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 $coll, 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 $coll to a string builder using start, end, and separator strings.
Appends all elements of this $coll 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 $coll 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
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.
Create a copy of the receiver object.
[use case] Builds a new collection by applying a partial function to all elements of this $coll on which the function is defined.
Builds a new collection by applying a partial function to all elements of this $coll on which the function is defined.
$collectExample
the element type of the returned collection.
the partial function which filters and maps the $coll.
a new $coll 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 $coll for which the given partial function is defined, and applies the partial function to it.
Finds the first element of the $coll for which the given partial function is defined, and applies the partial function to it.
$mayNotTerminateInf $orderDependent
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)
The factory companion object that builds instances of class $Coll.
The factory companion object that builds instances of class $Coll.
(or its Iterable superclass where class $Coll is not a Seq.)
[use case] Copies elements of this $coll to an array.
Copies elements of this $coll to an array.
Fills the given array xs with at most len elements of
this $coll, starting at position start.
Copying will stop once either the end of the current $coll is reached,
or the end of the array is reached, or len elements have been copied.
$willNotTerminateInf
the array to fill.
the starting index.
the maximal number of elements to copy.
[use case] Copies values of this $coll to an array.
Copies values of this $coll to an array.
Fills the given array xs with values of this $coll.
Copying will stop once either the end of the current $coll is reached,
or the end of the array is reached.
$willNotTerminateInf
the array to fill.
[use case] Copies values of this $coll to an array.
Copies values of this $coll to an array.
Fills the given array xs with values of this $coll, beginning at index start.
Copying will stop once either the end of the current $coll is reached,
or the end of the array is reached.
$willNotTerminateInf
the array to fill.
the starting index.
Copies all elements of this $coll to a buffer.
Copies all elements of this $coll to a buffer. $willNotTerminateInf
The buffer to which elements are copied.
Counts the number of elements in the $coll which satisfy a predicate.
Counts the number of elements in the $coll which satisfy a predicate.
the predicate used to test elements.
the number of elements satisfying the predicate p.
Selects all elements except first n ones.
Selects all elements except first n ones. $orderDependent
the number of elements to drop from this $coll.
a $coll consisting of all elements of this $coll except the first n ones, or else the
empty $coll, if this $coll has less than n elements.
Drops longest prefix of elements that satisfy a predicate.
Drops longest prefix of elements that satisfy a predicate. $orderDependent
the longest suffix of this $coll whose first element
does not satisfy the predicate p.
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 equality method for reference types.
Tests whether a predicate holds for some of the elements of this $coll.
Tests whether a predicate holds for some of the elements of this $coll.
$mayNotTerminateInf
the predicate used to test elements.
true if the given predicate p holds for some of the
elements of this $coll, otherwise false.
Selects all elements of this $coll which satisfy a predicate.
Selects all elements of this $coll which satisfy a predicate.
the predicate used to test elements.
a new $coll consisting of all elements of this $coll that satisfy the given
predicate p. The order of the elements is preserved.
Selects all elements of this $coll which do not satisfy a predicate.
Selects all elements of this $coll which do not satisfy a predicate.
the predicate used to test elements.
a new $coll consisting of all elements of this $coll 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 $coll satisfying a predicate, if any.
Finds the first element of the $coll satisfying a predicate, if any.
$mayNotTerminateInf $orderDependent
the predicate used to test elements.
an option value containing the first element in the $coll
that satisfies p, or None if none exists.
[use case] Builds a new collection by applying a function to all elements of this $coll and using the elements of the resulting collections.
Builds a new collection by applying a function to all elements of this $coll 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 $coll. 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 a 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 $coll resulting from applying the given collection-valued function
f to each element of this $coll and concatenating the results.
[use case] Converts this $coll of traversable collections into a $coll formed by the elements of these traversable collections.
Converts this $coll of traversable collections into a $coll formed by the elements of these traversable collections.
The resulting collection's type will be guided by the static type of $coll. For example:
val xs = List(Set(1, 2, 3), Set(1, 2, 3)) // xs == List(1, 2, 3, 1, 2, 3) val ys = Set(List(1, 2, 3), List(3, 2, 1)) // ys == Set(1, 2, 3)
the type of the elements of each traversable collection.
a new $coll resulting from concatenating all element ${coll}s.
Folds the elements of this $coll using the specified associative binary operator.
Folds the elements of this $coll using the specified associative binary operator.
$undefinedorder
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 $coll, going left to right.
Applies a binary operator to a start value and all elements of this $coll, going left to right.
$willNotTerminateInf $orderDependentFold
the result type of the binary operator.
the start value.
the binary operator.
the result of inserting op between consecutive elements of this $coll,
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 $coll.
Applies a binary operator to all elements of this $coll and a start value, going right to left.
Applies a binary operator to all elements of this $coll and a start value, going right to left.
$willNotTerminateInf $orderDependentFold
the result type of the binary operator.
the start value.
the binary operator.
the result of inserting op between consecutive elements of this $coll,
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 $coll.
Tests whether a predicate holds for all elements of this $coll.
Tests whether a predicate holds for all elements of this $coll.
$mayNotTerminateInf
the predicate used to test elements.
true if the given predicate p holds for all elements
of this $coll, otherwise false.
[use case]
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).
The generic builder that builds instances of $Coll at arbitrary element types.
The generic builder that builds instances of $Coll 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 $coll into a map of ${coll}s according to some discriminator function.
Partitions this $coll into a map of ${coll}s 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 $coll.
the type of keys returned by the discriminator function.
the discriminator function.
A map from keys to ${coll}s 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 $coll of those elements x
for which f(x) equals k.
Tests whether this $coll is known to have a finite size.
Tests whether this $coll 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.
The hashCode method for reference types.
Selects the first element of this $coll.
Selects the first element of this $coll. $orderDependent
the first element of this $coll.
if the $coll is empty.
Optionally selects the first element.
Optionally selects the first element. $orderDependent
the first element of this $coll if it is nonempty,
None if it is empty.
Selects all elements except the last.
Selects all elements except the last. $orderDependent
a $coll consisting of all elements of this $coll except the last one.
if the $coll is empty.
Iterates over the inits of this $coll.
Iterates over the inits of this $coll. The first value will be this
$coll and the final one will be an empty $coll, with the intervening
values the results of successive applications of init.
an iterator over all the inits of this $coll
List(1,2,3).inits = Iterator(List(1,2,3), List(1,2), List(1), Nil)
Tests whether this $coll is empty.
Tests whether this $coll is empty.
true if the $coll contain 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 $coll can be repeatedly traversed.
Tests whether this $coll can be repeatedly traversed.
true
Selects the last element.
Selects the last element. $orderDependent
The last element of this $coll.
If the $coll is empty.
Optionally selects the last element.
Optionally selects the last element. $orderDependent
the last element of this $coll$ if it is nonempty,
None if it is empty.
[use case] Builds a new collection by applying a function to all elements of this $coll.
Builds a new collection by applying a function to all elements of this $coll.
the element type of the returned collection.
the function to apply to each element.
a new $coll resulting from applying the given function
f to each element of this $coll and collecting the results.
[use case] Finds the largest element.
Finds the largest element.
the largest element of this $coll.
[use case] Finds the smallest element.
Finds the smallest element.
the smallest element of this $coll
Displays all elements of this $coll in a string.
Displays all elements of this $coll in a string.
a string representation of this $coll. In the resulting string
the string representations (w.r.t. the method toString)
of all elements of this $coll follow each other without any
separator string.
Displays all elements of this $coll in a string using a separator string.
Displays all elements of this $coll in a string using a separator string.
the separator string.
a string representation of this $coll. In the resulting string
the string representations (w.r.t. the method toString)
of all elements of this $coll are separated by the string sep.
List(1, 2, 3).mkString("|") = "1|2|3"
Displays all elements of this $coll in a string using start, end, and separator strings.
Displays all elements of this $coll in a string using start, end, and separator strings.
the starting string.
the separator string.
the ending string.
a string representation of this $coll. 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 $coll 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.
Tests whether the $coll is not empty.
Tests whether the $coll is not empty.
true if the $coll 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
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
Partitions this $coll in two ${coll}s according to a predicate.
Partitions this $coll in two ${coll}s according to a predicate.
the predicate on which to partition.
a pair of ${coll}s: the first $coll consists of all elements that
satisfy the predicate p and the second $coll consists of all elements
that don't. The relative order of the elements in the resulting ${coll}s
is the same as in the original $coll.
[use case] Multiplies up the elements of this collection.
Multiplies up the elements of this collection.
the product of all elements in this $coll 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 $coll and as result type of product.
Examples of such types are: Long, Float, Double, BigInt.
Reduces the elements of this $coll using the specified associative binary operator.
Reduces the elements of this $coll using the specified associative binary operator.
$undefinedorder
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 $coll is nonempty.
if this $coll is empty.
Optionally applies a binary operator to all elements of this $coll, going left to right.
Optionally applies a binary operator to all elements of this $coll, going left to right. $willNotTerminateInf $orderDependentFold
the result type of the binary operator.
the binary operator.
an option value containing the result of reduceLeft(op) is this $coll is nonempty,
None otherwise.
Reduces the elements of this $coll, if any, using the specified associative binary operator.
Reduces the elements of this $coll, if any, using the specified associative binary operator.
$undefinedorder
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 $coll, going right to left.
Applies a binary operator to all elements of this $coll, going right to left. $willNotTerminateInf $orderDependentFold
the result type of the binary operator.
the binary operator.
the result of inserting op between consecutive elements of this $coll,
going right to left:
op(x_1, op(x_2, ..., op(x_{n-1}, x_n)...)) where x1, ..., xn are the elements of this $coll.
if this $coll is empty.
Optionally applies a binary operator to all elements of this $coll, going right to left.
Optionally applies a binary operator to all elements of this $coll, going right to left. $willNotTerminateInf $orderDependentFold
the result type of the binary operator.
the binary operator.
an option value containing the result of reduceRight(op) is this $coll is nonempty,
None otherwise.
The collection of type $coll underlying this TraversableLike object.
The collection of type $coll underlying this TraversableLike object.
By default this is implemented as the TraversableLike object itself,
but this can be overridden.
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 $coll containing the prefix scan of the elements in this $coll
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.
$willNotTerminateInf $orderDependent
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
$bfinfo
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. $willNotTerminateInf $orderDependent
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
$bfinfo
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.
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 $coll.
The size of this $coll.
$willNotTerminateInf
the number of elements in this $coll.
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
$orderDependent
a $coll containing the elements greater than or equal to
index from extending up to (but not including) index until
of this $coll.
Splits this $coll into a prefix/suffix pair according to a predicate.
Splits this $coll 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.
$orderDependent
a pair consisting of the longest prefix of this $coll whose
elements all satisfy p, and the rest of this $coll.
Splits this $coll into two at a given position.
Splits this $coll into two at a given position.
Note: c splitAt n is equivalent to (but possibly more efficient than)
(c take n, c drop n).
$orderDependent
the position at which to split.
a pair of ${coll}s consisting of the first n
elements of this $coll, and the other elements.
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 $coll. By default the string prefix is the
simple name of the collection class $coll.
[use case] Sums up the elements of this collection.
Sums up the elements of this collection.
the sum of all elements in this $coll 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 $coll 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. $orderDependent
a $coll consisting of all elements of this $coll except the first one.
if the $coll is empty.
Iterates over the tails of this $coll.
Iterates over the tails of this $coll. The first value will be this
$coll and the final one will be an empty $coll, with the intervening
values the results of successive applications of tail.
an iterator over all the tails of this $coll
List(1,2,3).tails = Iterator(List(1,2,3), List(2,3), List(3), Nil)
Selects first n elements.
Selects first n elements. $orderDependent
Tt number of elements to take from this $coll.
a $coll consisting only of the first n elements of this $coll,
or else the whole $coll, 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. $orderDependent
the longest prefix of this $coll whose elements all satisfy
the predicate p.
[use case] Converts this $coll to an array.
Converts this $coll to an array.
$willNotTerminateInf
an array containing all elements of this $coll.
An ClassTag must be available for the element type of this $coll.
Converts this $coll to a mutable buffer.
Converts this $coll to a mutable buffer. $willNotTerminateInf
a buffer containing all elements of this $coll.
Converts this $coll to an indexed sequence.
Converts this $coll to an indexed sequence. $willNotTerminateInf
an indexed sequence containing all elements of this $coll.
Converts this $coll to an iterable collection.
Converts this $coll 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).
$willNotTerminateInf
an Iterable containing all elements of this $coll.
Returns an Iterator over the elements in this $coll.
Returns an Iterator over the elements in this $coll. Will return the same Iterator if this instance is already an Iterator. $willNotTerminateInf
an Iterator containing all elements of this $coll.
Converts this $coll to a list.
Converts this $coll to a list. $willNotTerminateInf
a list containing all elements of this $coll.
[use case] Converts this $coll to a map.
Converts this $coll 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.
$willNotTerminateInf
a map of type immutable.Map[T, U]
containing all key/value pairs of type (T, U) of this $coll.
Converts this $coll to a sequence.
Converts this $coll to a sequence. As with toIterable, it's lazy
in this default implementation, as this TraversableOnce may be
lazy and unevaluated.
$willNotTerminateInf
a sequence containing all elements of this $coll.
Converts this $coll to a set.
Converts this $coll to a set. $willNotTerminateInf
a set containing all elements of this $coll.
Converts this $coll to a stream.
Converts this $coll to a stream. $willNotTerminateInf
a stream containing all elements of this $coll.
Creates a String representation of this object.
Creates a String representation of this object. The default representation is platform dependent. On the java platform it is the concatenation of the class name, "@", and the object's hashcode in hexadecimal.
a String representation of the object.
Converts this $coll to an unspecified Traversable.
Converts this $coll to an unspecified Traversable. Will return the same collection if this instance is already Traversable. $willNotTerminateInf
a Traversable containing all elements of this $coll.
Transposes this $coll of traversable collections into a $coll of ${coll}s.
Transposes this $coll of traversable collections into a $coll of ${coll}s.
the type of the elements of each traversable collection.
an implicit conversion which asserts that the
element type of this $coll is a Traversable.
a two-dimensional $coll of ${coll}s which has as nth row the nth column of this $coll.
(Changed in version 2.9.0) transpose throws an IllegalArgumentException if collections are not uniformly sized.
if all collections in this $coll are not of the same size.
Converts this $coll of pairs into two collections of the first and second half of each pair.
Converts this $coll of pairs into two collections of the first and second half of each pair.
the type of the first half of the element pairs
the type of the second half of the element pairs
an implicit conversion which asserts that the element type of this $coll is a pair.
a pair ${coll}s, containing the first, respectively second half of each element pair of this $coll.
Converts this $coll of triples into three collections of the first, second, and third element of each triple.
Converts this $coll of triples into three collections of the first, second, and third element of each triple.
the type of the first member of the element triples
the type of the second member of the element triples
the type of the third member of the element triples
an implicit conversion which asserts that the element type of this $coll is a triple.
a triple ${coll}s, containing the first, second, respectively third member of each element triple of this $coll.
Creates a non-strict view of a slice of this $coll.
Creates a non-strict view of a slice of this $coll.
Note: the difference between view and slice is that view produces
a view of the current $coll, whereas slice produces a new $coll.
Note: view(from, to) is equivalent to view.slice(from, to)
$orderDependent
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 $coll, starting at index from
and extending up to (but not including) index until.
Creates a non-strict view of this $coll.
Creates a non-strict view of this $coll.
a non-strict view of this $coll.
Creates a non-strict filter of this $coll.
Creates a non-strict filter of this $coll.
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.
$orderDependent
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 $coll
which satisfy the predicate p.
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
(Since version 2.10.0) use fold instead
(Since version 2.10.0) Use leftOfArrow instead
(Since version 2.10.0) Use resultOfEnsuring instead
See comment on ZippedTraversable2.