scala.collection

Map

trait Map[A, +B] extends Iterable[(A, B)] with MapLike[A, B, Map[A, B]]

A map from keys of type A to values of type B.

$mapnote

Note: If you do not have specific implementations for add and - in mind, you might consider inheriting from DefaultMap instead.

Note: If your additions and mutations return the same kind of map as the map you are defining, you should inherit from MapLike as well.

A

the type of the keys in this map .

B

the type of the values associated with keys .

go to: companion
known subclasses: Map, Map, SortedMap, MapProxy, DefaultMap
source: Map.scala
    since
  1. 1

Inherited
  1. Hide All
  2. Show all
  1. MapLike
  2. Subtractable
  3. PartialFunction
  4. Function1
  5. Iterable
  6. IterableLike
  7. Equals
  8. Traversable
  9. GenericTraversableTemplate
  10. TraversableLike
  11. TraversableOnce
  12. HasNewBuilder
  13. AnyRef
  14. Any
Visibility
  1. Public
  2. All

Type Members

  1. class DefaultKeySet extends Set[A]

    The implementation class of the set returned by keySet.

  2. class DefaultValuesIterable extends Iterable[B]

    The implementation class of the iterable returned by values.

  3. type Self = Map[A, B]

    The type implementing this traversable

    The type implementing this traversable

    attributes: protected
    definition classes: TraversableLike
  4. class WithFilter extends AnyRef

    A class supporting filtered operations .

Value Members

  1. def !=(arg0: AnyRef): Boolean

    attributes: final
    definition classes: AnyRef
  2. def !=(arg0: Any): Boolean

    o != arg0 is the same as !(o == (arg0)).

    o != arg0 is the same as !(o == (arg0)).

    arg0

    the object to compare against this object for dis-equality .

    returns

    false if the receiver object is equivalent to the argument; true otherwise.

    attributes: final
    definition classes: Any
  3. def ##(): Int

    attributes: final
    definition classes: AnyRef → Any
  4. def $asInstanceOf[T0](): T0

    attributes: final
    definition classes: AnyRef
  5. def $isInstanceOf[T0](): Boolean

    attributes: final
    definition classes: AnyRef
  6. def +(kvs: Traversable[(A, B)]): Map[A, B]

    [use case] Adds all key/value pairs in a traversable collection to this map, returning a new map .

    [use case]

    Adds all key/value pairs in a traversable collection to this map, returning a new map .

    kvs

    the collection containing the added key/value pairs

    returns

    a new map with the given bindings added to this map

    attributes: abstract
  7. def +(kvs: (A, B)*): Map[A, B]

    [use case] Adds key/value pairs to this map, returning a new map .

    [use case]

    Adds key/value pairs to this map, returning a new map .

    kvs

    the remaining key/value pairs

    returns

    a new map with the given bindings added to this map

    attributes: abstract
  8. def +[B1 >: B](kv1: (A, B1), kv2: (A, B1), kvs: (A, B1)*): Map[A, B1]

    Adds key/value pairs to this map, returning a new map .

    Adds key/value pairs to this map, returning a new map .

    This method takes two or more key/value pairs. Another overloaded variant of this method handles the case where a single key/value pair is added.

    B1

    the type of the added values

    kv1

    the first key/value pair

    kv2

    the second key/value pair

    kvs

    the remaining key/value pairs

    returns

    a new map with the given bindings added to this map

    definition classes: MapLike
  9. def +(kv: (A, B)): Map[A, B]

    [use case] Adds a key/value pair to this map, returning a new map .

    [use case]

    Adds a key/value pair to this map, returning a new map .

    kv

    the key/value pair

    returns

    a new map with the new binding added to this map

    attributes: abstract
  10. def +[B1 >: B](kv: (A, B1)): Map[A, B1]

    Adds a key/value pair to this map, returning a new map .

    Adds a key/value pair to this map, returning a new map .

    B1

    the type of the value in the key/value pair .

    kv

    the key/value pair

    returns

    a new map with the new binding added to this map

    attributes: abstract
    definition classes: MapLike
  11. def ++[B1 >: B](xs: TraversableOnce[(A, B1)]): Map[A, B1]

    Adds all key/value pairs in a traversable collection to this map, returning a new map .

    Adds all key/value pairs in a traversable collection to this map, returning a new map .

    B1

    the type of the added values

    returns

    a new map with the given bindings added to this map

    definition classes: MapLike
  12. def ++(that: TraversableOnce[(A, B)]): Map[(A, B)]

    [use case] Concatenates this map with the elements of a traversable collection .

    [use case]

    Concatenates this map with the elements of a traversable collection .

    that

    the traversable to append .

    returns

    a new map which contains all elements of this map followed by all elements of that.

    attributes: abstract
  13. def ++[B >: (A, B), That](that: TraversableOnce[B])(implicit bf: CanBuildFrom[Map[A, B], B, That]): That

    Concatenates this map with the elements of a traversable collection .

    Concatenates this map with the elements of a traversable collection .

    B

    the element type of the returned collection .

    That

    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.

    that

    the traversable to append .

    bf

    an implicit value of class CanBuildFrom which determines the result class That from the current representation type Repr and and the new element type B.

    returns

    a new collection of type That which contains all elements of this map followed by all elements of that.

    definition classes: TraversableLike
  14. def -(elem1: A, elem2: A, elems: A*): Map[A, B]

    Creates a new map from this map with some elements removed .

    Creates a new map from this map with some elements removed .

    This method takes two or more elements to be removed. Another overloaded variant of this method handles the case where a single element is removed.

    elem1

    the first element to remove .

    elem2

    the second element to remove .

    elems

    the remaining elements to remove .

    returns

    a new map that contains all elements of the current map except one less occurrence of each of the given elements .

    definition classes: Subtractable
  15. def -(key: A): Map[A, B]

    [use case] Removes a key from this map, returning a new map .

    [use case]

    Removes a key from this map, returning a new map .

    key

    the key to be removed

    returns

    a new map without a binding for key

    attributes: abstract
    definition classes: MapMapLikeSubtractable
  16. def -(key: A): Map[A, B]

    Removes a key from this map, returning a new map .

    Removes a key from this map, returning a new map .

    key

    the key to be removed

    returns

    a new map without a binding for key

    attributes: abstract
    definition classes: MapLikeSubtractable
  17. def --(xs: TraversableOnce[A]): Map[A, B]

    Creates a new map from this map by removing all elements of another collection .

    Creates a new map from this map by removing all elements of another collection .

    returns

    a new map that contains all elements of the current map except one less occurrence of each of the elements of elems.

    definition classes: Subtractable
  18. def /:[B](z: B)(op: (B, (A, B)) ⇒ B): B

    Applies a binary operator to a start value and all elements of this map, going left to right .

    Applies a binary operator to a start value and all elements of this map, going left to right .

    Note: /: is alternate syntax for foldLeft; z /: xs is the same as xs foldLeft z.

    Note: might return different results for different runs, unless the underlying collection type is ordered. or the operator is associative and commutative.

    B

    the result type of the binary operator .

    z

    the start value .

    op

    the binary operator .

    returns

    the result of inserting op between consecutive elements of this map, 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 map.

    definition classes: TraversableOnce
  19. def :\[B](z: B)(op: ((A, B), B) ⇒ B): B

    Applies a binary operator to all elements of this map and a start value, going right to left .

    Applies a binary operator to all elements of this map and a start value, going right to left .

    Note: :\ is alternate syntax for foldRight; xs :\ z is the same as xs foldRight z.

    Note: might return different results for different runs, unless the underlying collection type is ordered. or the operator is associative and commutative.

    B

    the result type of the binary operator .

    z

    the start value

    op

    the binary operator

    returns

    the result of inserting op between consecutive elements of this map, 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 map.

    definition classes: TraversableOnce
  20. def ==(arg0: AnyRef): Boolean

    o == arg0 is the same as if (o eq null) arg0 eq null else o.equals(arg0).

    o == arg0 is the same as if (o eq null) arg0 eq null else o.equals(arg0).

    arg0

    the object to compare against this object for equality .

    returns

    true if the receiver object is equivalent to the argument; false otherwise.

    attributes: final
    definition classes: AnyRef
  21. def ==(arg0: Any): Boolean

    o == arg0 is the same as o.equals(arg0).

    o == arg0 is the same as o.equals(arg0).

    arg0

    the object to compare against this object for equality .

    returns

    true if the receiver object is equivalent to the argument; false otherwise.

    attributes: final
    definition classes: Any
  22. def addString(b: StringBuilder, start: String, sep: String, end: String): StringBuilder

    Appends all bindings of this map to a string builder using start, end, and separator strings .

    Appends all bindings of this map 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 of all bindings of this map in the form of key -> value are separated by the string sep.

    b

    the builder to which strings are appended .

    start

    the starting string .

    sep

    the separator string .

    end

    the ending string .

    returns

    the string builder b to which elements were appended.

    definition classes: MapLikeTraversableOnce
  23. def addString(b: StringBuilder): StringBuilder

    Appends all elements of this map to a string builder .

    Appends all elements of this map to a string builder. The written text consists of the string representations (w.r.t. the method toString) of all elements of this map without any separator string.

    b

    the string builder to which elements are appended .

    returns

    the string builder b to which elements were appended.

    definition classes: TraversableOnce
  24. def addString(b: StringBuilder, sep: String): StringBuilder

    Appends all elements of this map to a string builder using a separator string .

    Appends all elements of this map 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 map, separated by the string sep.

    b

    the string builder to which elements are appended .

    sep

    the separator string .

    returns

    the string builder b to which elements were appended.

    definition classes: TraversableOnce
  25. def andThen[C](k: (B) ⇒ C): PartialFunction[A, C]

    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 .

    C

    the result type of the transformation function .

    k

    the transformation function

    returns

    a partial function with the same domain as this partial function, which maps arguments x to k(this(x)).

    definition classes: PartialFunctionFunction1
  26. def apply(key: A): B

    Retrieves the value which is associated with the given key .

    Retrieves the value which is associated with the given key. This method invokes the default method of the map if there is no mapping from the given key to a value. Unless overridden, the default method throws a NoSuchElementException.

    key

    the key

    returns

    the value associated with the given key, or the result of the map's default method, if none exists.

    definition classes: MapLikeFunction1
  27. def asInstanceOf[T0]: T0

    This method is used to cast the receiver object to be of type T0.

    This method is used to 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 expression1.asInstanceOf[String] will throw a ClassCastException at runtime, while the expressionList(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 typed.

    returns

    the receiver object .

    attributes: final
    definition classes: Any
  28. def canEqual(that: Any): Boolean

    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 .

    that

    The object with which this map should be compared

    returns

    true, if this map can possibly equal that, false otherwise. The test takes into consideration only the run-time types of objects but ignores their elements.

    definition classes: IterableLikeEquals
  29. def clone(): AnyRef

    This method creates and returns a copy of the receiver object .

    This method creates and returns a copy of the receiver object .

    The default implementation of the clone method is platform dependent.

    returns

    a copy of the receiver object .

    attributes: protected
    definition classes: AnyRef
  30. def collect[B](pf: PartialFunction[(A, B), B]): Map[B]

    [use case] Builds a new collection by applying a partial function to all elements of this map on which the function is defined .

    [use case]

    Builds a new collection by applying a partial function to all elements of this map on which the function is defined .

    B

    the element type of the returned collection .

    pf

    the partial function which filters and maps the map .

    returns

    a new map 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.

    attributes: abstract
  31. def collect[B, That](pf: PartialFunction[(A, B), B])(implicit bf: CanBuildFrom[Map[A, B], B, That]): That

    Builds a new collection by applying a partial function to all elements of this map on which the function is defined .

    Builds a new collection by applying a partial function to all elements of this map on which the function is defined .

    B

    the element type of the returned collection .

    That

    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.

    pf

    the partial function which filters and maps the map .

    bf

    an implicit value of class CanBuildFrom which determines the result class That from the current representation type Repr and and the new element type B.

    returns

    a new collection of type That resulting from applying the partial function pf to each element on which it is defined and collecting the results. The order of the elements is preserved.

    definition classes: TraversableLike
  32. def companion: GenericCompanion[Iterable[A][A]]

    The factory companion object that builds instances of class Map .

    The factory companion object that builds instances of class Map .

    definition classes: IterableTraversableGenericTraversableTemplate
  33. def compose[A](g: (A) ⇒ A): (A) ⇒ B

    (f compose g)(x) == f(g(x))

    (f compose g)(x) == f(g(x))

    definition classes: Function1
  34. def contains(key: A): Boolean

    Tests whether this map contains a binding for a key .

    Tests whether this map contains a binding for a key .

    key

    the key

    returns

    true if there is a binding for key in this map, false otherwise.

    definition classes: MapLike
  35. def copyToArray(xs: Array[(A, B)], start: Int, len: Int): Unit

    [use case] Copies elements of this map to an array .

    [use case]

    Copies elements of this map to an array. Fills the given array xs with at most len elements of this map, starting at position start. Copying will stop once either the end of the current map is reached, or the end of the array is reached, or len elements have been copied.

    xs

    the array to fill .

    start

    the starting index .

    len

    the maximal number of elements to copy .

    attributes: abstract
  36. def copyToArray[B >: (A, B)](xs: Array[B], start: Int, len: Int): Unit

    Copies elements of this map to an array .

    Copies elements of this map to an array. Fills the given array xs with at most len elements of this map, starting at position start. Copying will stop once either the end of the current map is reached, or the end of the array is reached, or len elements have been copied.

    B

    the type of the elements of the array .

    xs

    the array to fill .

    start

    the starting index .

    len

    the maximal number of elements to copy .

    definition classes: IterableLikeTraversableLikeTraversableOnce
  37. def copyToArray(xs: Array[(A, B)]): Unit

    [use case] Copies values of this map to an array .

    [use case]

    Copies values of this map to an array. Fills the given array xs with values of this map. Copying will stop once either the end of the current map is reached, or the end of the array is reached.

    xs

    the array to fill .

    attributes: abstract
  38. def copyToArray[B >: (A, B)](xs: Array[B]): Unit

    Copies values of this map to an array .

    Copies values of this map to an array. Fills the given array xs with values of this map. Copying will stop once either the end of the current map is reached, or the end of the array is reached.

    B

    the type of the elements of the array .

    xs

    the array to fill .

    definition classes: TraversableOnce
  39. def copyToArray(xs: Array[(A, B)], start: Int): Unit

    [use case] Copies values of this map to an array .

    [use case]

    Copies values of this map to an array. Fills the given array xs with values of this map, after skipping start values. Copying will stop once either the end of the current map is reached, or the end of the array is reached.

    xs

    the array to fill .

    start

    the starting index .

    attributes: abstract
  40. def copyToArray[B >: (A, B)](xs: Array[B], start: Int): Unit

    Copies values of this map to an array .

    Copies values of this map to an array. Fills the given array xs with values of this map, after skipping start values. Copying will stop once either the end of the current map is reached, or the end of the array is reached.

    B

    the type of the elements of the array .

    xs

    the array to fill .

    start

    the starting index .

    definition classes: TraversableOnce
  41. def copyToBuffer[B >: (A, B)](dest: Buffer[B]): Unit

    Copies all elements of this map to a buffer .

    Copies all elements of this map to a buffer .

    dest

    The buffer to which elements are copied .

    definition classes: TraversableOnce
  42. def count(p: ((A, B)) ⇒ Boolean): Int

    Counts the number of elements in the map which satisfy a predicate .

    Counts the number of elements in the map which satisfy a predicate .

    p

    the predicate used to test elements .

    returns

    the number of elements satisfying the predicate p.

    definition classes: TraversableOnce
  43. def default(key: A): B

    Defines the default value computation for the map, returned when a key is not found The method implemented here throws an exception, but it might be overridden in subclasses .

    Defines the default value computation for the map, returned when a key is not found The method implemented here throws an exception, but it might be overridden in subclasses .

    key

    the given key value for which a binding is missing .

    definition classes: MapLike
  44. def drop(n: Int): Map[A, B]

    Selects all elements except first n ones.

    Selects all elements except first n ones.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    n

    the number of elements to drop from this map .

    returns

    a map consisting of all elements of this map except the first n ones, or else the empty map, if this map has less than n elements.

    definition classes: TraversableLike
  45. def dropRight(n: Int): Map[A, B]

    Selects all elements except last n ones.

    Selects all elements except last n ones.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    n

    The number of elements to take

    returns

    a map consisting of all elements of this map except the first n ones, or else the empty map, if this map has less than n elements.

    definition classes: IterableLike
  46. def dropWhile(p: ((A, B)) ⇒ Boolean): Map[A, B]

    Drops longest prefix of elements that satisfy a predicate .

    Drops longest prefix of elements that satisfy a predicate .

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    p

    The predicate used to test elements .

    returns

    the longest suffix of this map whose first element does not satisfy the predicate p.

    definition classes: TraversableLike
  47. def elements: Iterator[(A, B)]

    definition classes: IterableLike
      deprecated:
    1. use iterator' instead

  48. def empty: Map[A, B]

    The empty map of the same type as this map

    The empty map of the same type as this map

    returns

    an empty map of type This.

    definition classes: MapMapLike
  49. def eq(arg0: AnyRef): Boolean

    This method is used to test whether the argument (arg0) is a reference to the receiver object (this).

    This method is used to test whether the argument (arg0) is a reference to the receiver object (this).

    The eq method implements an [http://en.wikipedia.org/wiki/Equivalence_relation equivalence relation] on non-null instances of AnyRef: * It is reflexive: for any non-null instance x of type AnyRef, x.eq(x) returns true. * It is symmetric: for any non-null instances x and y of type AnyRef, x.eq(y) returns true if and only if y.eq(x) returns true. * It is transitive: for any non-null instances x, y, and z of type AnyRef if x.eq(y) returns true and y.eq(z) returns true, then x.eq(z) returns true.

    Additionally, the eq method has three other properties. * It is consistent: for any non-null instances x and y of type AnyRef, multiple invocations of x.eq(y) consistently returns true or consistently returns false. * For any non-null instance 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).

    arg0

    the object to compare against this object for reference equality .

    returns

    true if the argument is a reference to the receiver object; false otherwise.

    attributes: final
    definition classes: AnyRef
  50. def equals(that: Any): Boolean

    Compares two maps structurally; i .

    Compares two maps structurally; i . e. checks if all mappings contained in this map are also contained in the other map, and vice versa.

    that

    the other map

    returns

    true if both maps contain exactly the same mappings, false otherwise.

    definition classes: MapLikeEquals → AnyRef → Any
  51. def exists(p: ((A, B)) ⇒ Boolean): Boolean

    Tests whether a predicate holds for some of the elements of this map .

    Tests whether a predicate holds for some of the elements of this map .

    p

    the predicate used to test elements .

    returns

    true if the given predicate p holds for some of the elements of this map, otherwise false.

    definition classes: IterableLikeTraversableLikeTraversableOnce
  52. def filter(p: ((A, B)) ⇒ Boolean): Map[A, B]

    Selects all elements of this map which satisfy a predicate .

    Selects all elements of this map which satisfy a predicate .

    p

    the predicate used to test elements .

    returns

    a new map consisting of all elements of this map that satisfy the given predicate p. The order of the elements is preserved.

    definition classes: TraversableLike
  53. def filterKeys(p: (A) ⇒ Boolean): Map[A, B]

    Filters this map by retaining only keys satisfying a predicate .

    Filters this map by retaining only keys satisfying a predicate .

    p

    the predicate used to test keys

    returns

    an immutable map consisting only of those key value pairs of this map where the key satisfies the predicate p. The resulting map wraps the original map without copying any elements.

    definition classes: MapLike
  54. def filterNot(p: ((A, B)) ⇒ Boolean): Map[A, B]

    Returns a new map with all key/value pairs for which the predicate p returns true.

    Returns a new map with all key/value pairs for which the predicate p returns true.

    Note: This method works by successively removing elements fro which the predicate is false from this set. If removal is slow, or you expect that most elements of the set will be removed, you might consider using filter with a negated predicate instead.

    p

    A predicate over key-value pairs

    returns

    A new map containing elements not satisfying the predicate .

    definition classes: MapLikeTraversableLike
  55. def finalize(): Unit

    This method is called by the garbage collector on the receiver object when garbage collection determines that there are no more references to the object .

    This method is called by the garbage collector on the receiver object when garbage collection determines that there are no more references to the object .

    The details of when and if the finalize method are invoked, as well as the interaction between finalizeand non-local returns and exceptions, are all platform dependent.

    attributes: protected
    definition classes: AnyRef
  56. def find(p: ((A, B)) ⇒ Boolean): Option[(A, B)]

    Finds the first element of the map satisfying a predicate, if any .

    Finds the first element of the map satisfying a predicate, if any .

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    p

    the predicate used to test elements .

    returns

    an option value containing the first element in the map that satisfies p, or None if none exists.

    definition classes: IterableLikeTraversableLikeTraversableOnce
  57. def first: (A, B)

    definition classes: IterableLike
      deprecated:
    1. use head' instead

  58. def firstOption: Option[(A, B)]

    None if iterable is empty.

    None if iterable is empty.

    definition classes: IterableLike
      deprecated:
    1. use headOption' instead

  59. def flatMap[B](f: ((A, B)) ⇒ Traversable[B]): Map[B]

    [use case] Builds a new collection by applying a function to all elements of this map and concatenating the results .

    [use case]

    Builds a new collection by applying a function to all elements of this map and concatenating the results .

    B

    the element type of the returned collection .

    f

    the function to apply to each element .

    returns

    a new map resulting from applying the given collection-valued function f to each element of this map and concatenating the results.

    attributes: abstract
  60. def flatMap[B, That](f: ((A, B)) ⇒ Traversable[B])(implicit bf: CanBuildFrom[Map[A, B], B, That]): That

    Builds a new collection by applying a function to all elements of this map and concatenating the results .

    Builds a new collection by applying a function to all elements of this map and concatenating the results .

    B

    the element type of the returned collection .

    That

    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.

    f

    the function to apply to each element .

    bf

    an implicit value of class CanBuildFrom which determines the result class That from the current representation type Repr and and the new element type B.

    returns

    a new collection of type That resulting from applying the given collection-valued function f to each element of this map and concatenating the results.

    definition classes: TraversableLike
  61. def flatten[B]: Map[B]

    [use case] Converts this map of traversable collections into a map in which all element collections are concatenated .

    [use case]

    Converts this map of traversable collections into a map in which all element collections are concatenated .

    B

    the type of the elements of each traversable collection .

    returns

    a new map resulting from concatenating all element maps .

    attributes: abstract
  62. def flatten[B](implicit asTraversable: ((A, B)) ⇒ Traversable[B]): Iterable[B]

    Converts this map of traversable collections into a map in which all element collections are concatenated .

    Converts this map of traversable collections into a map in which all element collections are concatenated .

    B

    the type of the elements of each traversable collection .

    asTraversable

    an implicit conversion which asserts that the element type of this map is a Traversable.

    returns

    a new map resulting from concatenating all element maps .

    definition classes: GenericTraversableTemplate
  63. def foldLeft[B](z: B)(op: (B, (A, B)) ⇒ B): B

    Applies a binary operator to a start value and all elements of this map, going left to right .

    Applies a binary operator to a start value and all elements of this map, going left to right .

    Note: might return different results for different runs, unless the underlying collection type is ordered. or the operator is associative and commutative.

    B

    the result type of the binary operator .

    z

    the start value .

    op

    the binary operator .

    returns

    the result of inserting op between consecutive elements of this map, 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 map.

    definition classes: TraversableOnce
  64. def foldRight[B](z: B)(op: ((A, B), B) ⇒ B): B

    Applies a binary operator to all elements of this map and a start value, going right to left .

    Applies a binary operator to all elements of this map and a start value, going right to left .

    Note: might return different results for different runs, unless the underlying collection type is ordered. or the operator is associative and commutative.

    B

    the result type of the binary operator .

    z

    the start value .

    op

    the binary operator .

    returns

    the result of inserting op between consecutive elements of this map, 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 map.

    definition classes: IterableLikeTraversableOnce
  65. def forall(p: ((A, B)) ⇒ Boolean): Boolean

    Tests whether a predicate holds for all elements of this map .

    Tests whether a predicate holds for all elements of this map .

    p

    the predicate used to test elements .

    returns

    true if the given predicate p holds for all elements of this map, otherwise false.

    definition classes: IterableLikeTraversableLikeTraversableOnce
  66. def foreach(f: ((A, B)) ⇒ Unit): Unit

    [use case] Applies a function f to all elements of this map.

    [use case]

    Applies a function f to all elements of this map.

    f

    the function that is applied for its side-effect to every element. The result of function f is discarded.

    attributes: abstract
  67. def foreach[U](f: ((A, B)) ⇒ U): Unit

    Applies a function f to all elements of this map.

    Applies a function f to all elements of this map.

    Note: this method underlies the implementation of most other bulk operations. Subclasses should re-implement this method if a more efficient implementation exists.

    U

    the type parameter describing the result of function f. This result will always be ignored. Typically U is Unit, but this is not necessary.

    f

    the function that is applied for its side-effect to every element. The result of function f is discarded.

    definition classes: IterableLikeTraversableLikeTraversableOnce
  68. def genericBuilder[B]: Builder[B, Iterable[B]]

    The generic builder that builds instances of Map at arbitrary element types .

    The generic builder that builds instances of Map at arbitrary element types .

    definition classes: GenericTraversableTemplate
  69. def get(key: A): Option[B]

    Optionally returns the value associated with a key .

    Optionally returns the value associated with a key .

    key

    the key value

    returns

    an option value containing the value associated with key in this map, or None if none exists.

    attributes: abstract
    definition classes: MapLike
  70. def getClass(): java.lang.Class[_ <: java.lang.Object]

    Returns a representation that corresponds to the dynamic class of the receiver object .

    Returns a representation that corresponds to the dynamic class of the receiver object .

    The nature of the representation is platform dependent.

    returns

    a representation that corresponds to the dynamic class of the receiver object .

    attributes: final
    definition classes: AnyRef
  71. def getOrElse(key: A, default: ⇒ B): B

    [use case] Returns the value associated with a key, or a default value if the key is not contained in the map .

    [use case]

    Returns the value associated with a key, or a default value if the key is not contained in the map .

    key

    the key .

    default

    a computation that yields a default value in case no binding for key is found in the map.

    returns

    the value associated with key if it exists, otherwise the result of the default computation.

    attributes: abstract
  72. def getOrElse[B1 >: B](key: A, default: ⇒ B1): B1

    Returns the value associated with a key, or a default value if the key is not contained in the map .

    Returns the value associated with a key, or a default value if the key is not contained in the map .

    B1

    the result type of the default computation .

    key

    the key .

    default

    a computation that yields a default value in case no binding for key is found in the map.

    returns

    the value associated with key if it exists, otherwise the result of the default computation.

    definition classes: MapLike
  73. def groupBy[K](f: ((A, B)) ⇒ K): Map[K, Map[A, B]]

    Partitions this map into a map of maps according to some discriminator function .

    Partitions this map into a map of maps 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 map.

    K

    the type of keys returned by the discriminator function .

    f

    the discriminator function .

    returns

    A map from keys to maps 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 map of those elements x for which f(x) equals k.

    definition classes: TraversableLike
  74. def grouped(size: Int): Iterator[Map[A, B]]

    Partitions elements in fixed size maps .

    Partitions elements in fixed size maps .

    size

    the number of elements per group

    returns

    An iterator producing maps of size size, except the last will be truncated if the elements don't divide evenly.

    definition classes: IterableLike
      see also:
    1. Iterator#grouped

  75. def hasDefiniteSize: Boolean

    Tests whether this map is known to have a finite size .

    Tests whether this map 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.

    returns

    true if this collection is known to have finite size, false otherwise.

    definition classes: TraversableLikeTraversableOnce
  76. def hashCode(): Int

    Returns a hash code value for the object .

    Returns a hash code value for the object .

    The default hashing algorithm is platform dependent.

    Note that it is allowed for two objects to have identical hash codes (o1.hashCode.equals(o2.hashCode)) yet not be equal (o1.equals(o2) returns false). A degenerate implementation could always return 0. However, it is required that if two objects are equal (o1.equals(o2) returns true) that they have identical hash codes (o1.hashCode.equals(o2.hashCode)). Therefore, when overriding this method, be sure to verify that the behavior is consistent with the equals method.

    returns

    the hash code value for the object .

    definition classes: MapLike → AnyRef → Any
  77. def head: (A, B)

    Selects the first element of this map .

    Selects the first element of this map .

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    returns

    the first element of this map .

    definition classes: IterableLikeTraversableLike
  78. def headOption: Option[(A, B)]

    Optionally selects the first element .

    Optionally selects the first element .

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    returns

    the first element of this map if it is nonempty, None if it is empty.

    definition classes: TraversableLike
  79. def init: Map[A, B]

    Selects all elements except the last .

    Selects all elements except the last .

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    returns

    a map consisting of all elements of this map except the last one .

    definition classes: TraversableLike
  80. def isDefinedAt(key: A): Boolean

    Tests whether this map contains a binding for a key .

    Tests whether this map contains a binding for a key. This method, which implements an abstract method of trait PartialFunction, is equivalent to contains.

    key

    the key

    returns

    true if there is a binding for key in this map, false otherwise.

    definition classes: MapLikePartialFunction
  81. def isEmpty: Boolean

    Tests whether the map is empty .

    Tests whether the map is empty .

    returns

    true if the map does not contain any key/value binding, false otherwise.

    definition classes: MapLikeIterableLikeTraversableLikeTraversableOnce
  82. def isInstanceOf[T0]: Boolean

    This method is used to test whether the dynamic type of the receiver object is T0.

    This method is used to test whether the dynamic type of the receiver object is T0.

    Note that the test result of the test is modulo Scala's erasure semantics. Therefore the expression1.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 requested typed.

    returns

    true if the receiver object is an instance of erasure of type T0; false otherwise.

    attributes: final
    definition classes: Any
  83. def isTraversableAgain: Boolean

    Tests whether this map can be repeatedly traversed .

    Tests whether this map can be repeatedly traversed .

    returns

    true

    attributes: final
    definition classes: TraversableLikeTraversableOnce
  84. def iterator: Iterator[(A, B)]

    Creates a new iterator over all key/value pairs of this map

    Creates a new iterator over all key/value pairs of this map

    returns

    the new iterator

    attributes: abstract
    definition classes: MapLikeIterableLike
  85. def keySet: Set[A]

    Collects all keys of this map in a set .

    Collects all keys of this map in a set .

    returns

    a set containing all keys of this map .

    definition classes: MapLike
  86. def keys: Iterable[A]

    Creates an iterator for all keys .

    Creates an iterator for all keys .

    returns

    an iterator over all keys .

    definition classes: MapLike
  87. def keysIterator: Iterator[A]

    Creates an iterator for all keys .

    Creates an iterator for all keys .

    returns

    an iterator over all keys .

    definition classes: MapLike
  88. def last: (A, B)

    Selects the last element .

    Selects the last element .

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    returns

    the first element of this map .

    definition classes: TraversableLike
  89. def lastOption: Option[(A, B)]

    Optionally selects the last element .

    Optionally selects the last element .

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    returns

    the last element of this map$ if it is nonempty, None if it is empty.

    definition classes: TraversableLike
  90. def lift: (A) ⇒ Option[B]

    Turns this partial function into an plain function returning an Option result.

    Turns this partial function into an plain function returning an Option result.

    returns

    a function that takes an argument x to Some(this(x)) if this is defined for x, and to None otherwise.

    definition classes: PartialFunction
  91. def map[B](f: ((A, B)) ⇒ B): Map[B]

    [use case] Builds a new collection by applying a function to all elements of this map .

    [use case]

    Builds a new collection by applying a function to all elements of this map .

    B

    the element type of the returned collection .

    f

    the function to apply to each element .

    returns

    a new map resulting from applying the given function f to each element of this map and collecting the results.

    attributes: abstract
  92. def map[B, That](f: ((A, B)) ⇒ B)(implicit bf: CanBuildFrom[Map[A, B], B, That]): That

    Builds a new collection by applying a function to all elements of this map .

    Builds a new collection by applying a function to all elements of this map .

    B

    the element type of the returned collection .

    That

    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.

    f

    the function to apply to each element .

    bf

    an implicit value of class CanBuildFrom which determines the result class That from the current representation type Repr and and the new element type B.

    returns

    a new collection of type That resulting from applying the given function f to each element of this map and collecting the results.

    definition classes: TraversableLike
  93. def mapElements[C](f: (B) ⇒ C): Map[A, C]

    definition classes: MapLike
      deprecated:
    1. use mapValues' instead

  94. def mapValues[C](f: (B) ⇒ C): Map[A, C]

    Transforms this map by applying a function to every retrieved value .

    Transforms this map by applying a function to every retrieved value .

    f

    the function used to transform values of this map .

    returns

    a map view which maps every key of this map to f(this(key)). The resulting map wraps the original map without copying any elements.

    definition classes: MapLike
  95. def max: (A, B)

    [use case] Finds the largest element .

    [use case]

    Finds the largest element .

    returns

    the largest element of this map .

    attributes: abstract
  96. def max[B >: (A, B)](implicit cmp: Ordering[B]): (A, B)

    Finds the largest element .

    Finds the largest element .

    B

    The type over which the ordering is defined .

    cmp

    An ordering to be used for comparing elements .

    returns

    the largest element of this map with respect to the ordering cmp.

    definition classes: TraversableOnce
  97. def min: (A, B)

    [use case] Finds the smallest element .

    [use case]

    Finds the smallest element .

    returns

    the smallest element of this map

    attributes: abstract
  98. def min[B >: (A, B)](implicit cmp: Ordering[B]): (A, B)

    Finds the smallest element .

    Finds the smallest element .

    B

    The type over which the ordering is defined .

    cmp

    An ordering to be used for comparing elements .

    returns

    the smallest element of this map with respect to the ordering cmp.

    definition classes: TraversableOnce
  99. def mkString: String

    Displays all elements of this map in a string .

    Displays all elements of this map in a string .

    returns

    a string representation of this map. In the resulting string the string representations (w.r.t. the method toString) of all elements of this map follow each other without any separator string.

    definition classes: TraversableOnce
  100. def mkString(sep: String): String

    Displays all elements of this map in a string using a separator string .

    Displays all elements of this map in a string using a separator string .

    sep

    the separator string .

    returns

    a string representation of this map. In the resulting string the string representations (w.r.t. the method toString) of all elements of this map are separated by the string sep.

    definition classes: TraversableOnce
  101. def mkString(start: String, sep: String, end: String): String

    Displays all elements of this map in a string using start, end, and separator strings .

    Displays all elements of this map in a string using start, end, and separator strings .

    start

    the starting string .

    sep

    the separator string .

    end

    the ending string .

    returns

    a string representation of this map. 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 map are separated by the string sep.

    definition classes: TraversableOnce
  102. def ne(arg0: AnyRef): Boolean

    o.ne(arg0) is the same as !(o.eq(arg0)).

    o.ne(arg0) is the same as !(o.eq(arg0)).

    arg0

    the object to compare against this object for reference dis-equality .

    returns

    false if the argument is not a reference to the receiver object; true otherwise.

    attributes: final
    definition classes: AnyRef
  103. def newBuilder: Builder[(A, B), Map[A, B]]

    A common implementation of newBuilder for all maps in terms of empty.

    A common implementation of newBuilder for all maps in terms of empty. Overridden for mutable maps in mutable.MapLike.

    attributes: protected[this]
    definition classes: MapLikeTraversableLikeHasNewBuilder
  104. def nonEmpty: Boolean

    Tests whether the map is not empty .

    Tests whether the map is not empty .

    returns

    true if the map contains at least one element, false otherwise.

    definition classes: TraversableOnce
  105. def notify(): Unit

    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 .

    attributes: final
    definition classes: AnyRef
  106. def notifyAll(): Unit

    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 .

    attributes: final
    definition classes: AnyRef
  107. def orElse[A1 <: A, B1 >: B](that: PartialFunction[A1, B1]): PartialFunction[A1, B1]

    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 .

    A1

    the argument type of the fallback function

    B1

    the result type of the fallback function

    that

    the fallback function

    returns

    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.

    definition classes: PartialFunction
  108. def partition(p: ((A, B)) ⇒ Boolean): (Map[A, B], Map[A, B])

    Partitions this map in two maps according to a predicate .

    Partitions this map in two maps according to a predicate .

    p

    the predicate on which to partition .

    returns

    a pair of maps: the first map consists of all elements that satisfy the predicate p and the second map consists of all elements that don't. The relative order of the elements in the resulting maps is the same as in the original map.

    definition classes: TraversableLike
  109. def product: Int

    [use case] Multiplies up the elements of this collection .

    [use case]

    Multiplies up the elements of this collection .

    returns

    the product of all elements in this map 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 map and as result type of product. Examples of such types are: Long, Float, Double, BigInt.

    attributes: abstract
  110. def product[B >: (A, B)](implicit num: Numeric[B]): B

    Multiplies up the elements of this collection .

    Multiplies up the elements of this collection .

    B

    the result type of the * operator.

    num

    an implicit parameter defining a set of numeric operations which includes the * operator to be used in forming the product.

    returns

    the product of all elements of this map with respect to the * operator in num.

    definition classes: TraversableOnce
  111. def projection: IterableView[(A, B), Map[A, B]]

    returns a projection that can be used to call non-strict filter,map, and flatMap methods that build projections of the collection.

    returns a projection that can be used to call non-strict filter,map, and flatMap methods that build projections of the collection.

    definition classes: IterableLike
      deprecated:
    1. use view' instead

  112. def reduceLeft[B >: (A, B)](op: (B, (A, B)) ⇒ B): B

    Applies a binary operator to all elements of this map, going left to right .

    Applies a binary operator to all elements of this map, going left to right .

    Note: might return different results for different runs, unless the underlying collection type is ordered. or the operator is associative and commutative.

    B

    the result type of the binary operator .

    op

    the binary operator .

    returns

    the result of inserting op between consecutive elements of this map, going left to right: op(...(op(x1, x2), ... ) , xn) where x,,1,,, ..., x,,n,, are the elements of this map.

    definition classes: TraversableOnce
  113. def reduceLeftOption[B >: (A, B)](op: (B, (A, B)) ⇒ B): Option[B]

    Optionally applies a binary operator to all elements of this map, going left to right .

    Optionally applies a binary operator to all elements of this map, going left to right .

    Note: might return different results for different runs, unless the underlying collection type is ordered. or the operator is associative and commutative.

    B

    the result type of the binary operator .

    op

    the binary operator .

    returns

    an option value containing the result of reduceLeft(op) is this map is nonempty, None otherwise.

    definition classes: TraversableOnce
  114. def reduceRight[B >: (A, B)](op: ((A, B), B) ⇒ B): B

    Applies a binary operator to all elements of this map, going right to left .

    Applies a binary operator to all elements of this map, going right to left .

    Note: might return different results for different runs, unless the underlying collection type is ordered. or the operator is associative and commutative.

    B

    the result type of the binary operator .

    op

    the binary operator .

    returns

    the result of inserting op between consecutive elements of this map, going right to left: op(x1, op(x2, ..., op(xn-1, xn)...)) where x,,1,,, ..., x,,n,, are the elements of this map.

    definition classes: IterableLikeTraversableOnce
  115. def reduceRightOption[B >: (A, B)](op: ((A, B), B) ⇒ B): Option[B]

    Optionally applies a binary operator to all elements of this map, going right to left .

    Optionally applies a binary operator to all elements of this map, going right to left .

    Note: might return different results for different runs, unless the underlying collection type is ordered. or the operator is associative and commutative.

    B

    the result type of the binary operator .

    op

    the binary operator .

    returns

    an option value containing the result of reduceRight(op) is this map is nonempty, None otherwise.

    definition classes: TraversableOnce
  116. def repr: Map[A, B]

    The collection of type map underlying this TraversableLike object.

    The collection of type map underlying this TraversableLike object. By default this is implemented as the TraversableLike object itself, but this can be overridden.

    definition classes: TraversableLike
  117. def reversed: List[(A, B)]

    attributes: protected[this]
    definition classes: TraversableOnce
  118. def sameElements(that: Iterable[(A, B)]): Boolean

    [use case] Checks if the other iterable collection contains the same elements in the same order as this map .

    [use case]

    Checks if the other iterable collection contains the same elements in the same order as this map .

    that

    the collection to compare with .

    returns

    true, if both collections contain the same elements in the same order, false otherwise.

    attributes: abstract
  119. def sameElements[B >: (A, B)](that: Iterable[B]): Boolean

    Checks if the other iterable collection contains the same elements in the same order as this map .

    Checks if the other iterable collection contains the same elements in the same order as this map .

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    B

    the type of the elements of collection that.

    that

    the collection to compare with .

    returns

    true, if both collections contain the same elements in the same order, false otherwise.

    definition classes: IterableLike
  120. def scanLeft[B, That](z: B)(op: (B, (A, B)) ⇒ B)(implicit bf: CanBuildFrom[Map[A, B], B, That]): That

    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 .

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    B

    the type of the elements in the resulting collection

    That

    the actual type of the resulting collection

    z

    the initial value

    op

    the binary operator applied to the intermediate result and the element

    bf

    an implicit value of class CanBuildFrom which determines the result class That from the current representation type Repr and and the new element type B.

    returns

    collection with intermediate results

    definition classes: TraversableLike
  121. def scanRight[B, That](z: B)(op: ((A, B), B) ⇒ B)(implicit bf: CanBuildFrom[Map[A, B], B, That]): That

    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 .

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    B

    the type of the elements in the resulting collection

    That

    the actual type of the resulting collection

    z

    the initial value

    op

    the binary operator applied to the intermediate result and the element

    bf

    an implicit value of class CanBuildFrom which determines the result class That from the current representation type Repr and and the new element type B.

    returns

    collection with intermediate results

    definition classes: TraversableLike
  122. def size: Int

    The size of this map .

    The size of this map .

    returns

    the number of elements in this map .

    definition classes: TraversableOnce
  123. def slice(from: Int, until: Int): Map[A, B]

    Selects an interval of elements .

    Selects an interval of elements .

    Note: c.slice(from, to) is equivalent to (but possibly more efficient than) c.drop(from).take(to - from)

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    from

    the index of the first returned element in this map .

    until

    the index one past the last returned element in this map .

    returns

    a map containing the elements starting at index from and extending up to (but not including) index until of this map.

    definition classes: IterableLikeTraversableLike
  124. def sliding[B >: (A, B)](size: Int, step: Int): Iterator[Map[A, B]]

    definition classes: IterableLike
  125. def sliding[B >: (A, B)](size: Int): Iterator[Map[A, B]]

    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 . )

    size

    the number of elements per group

    returns

    An iterator producing maps of size size, except the last will be truncated if the elements don't divide evenly.

    definition classes: IterableLike
      see also:
    1. Iterator#sliding

  126. def span(p: ((A, B)) ⇒ Boolean): (Map[A, B], Map[A, B])

    Splits this map into a prefix/suffix pair according to a predicate .

    Splits this map 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.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    p

    the test predicate

    returns

    a pair consisting of the longest prefix of this map whose elements all satisfy p, and the rest of this map.

    definition classes: TraversableLike
  127. def splitAt(n: Int): (Map[A, B], Map[A, B])

    Splits this map into two at a given position .

    Splits this map into two at a given position. Note: c splitAt n is equivalent to (but possibly more efficient than) (c take n, c drop n).

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    n

    the position at which to split .

    returns

    a pair of maps consisting of the first n elements of this map, and the other elements.

    definition classes: TraversableLike
  128. def stringPrefix: String

    Defines the prefix of this object's toString representation.

    Defines the prefix of this object's toString representation.

    returns

    a string representation which starts the result of toString applied to this map. Unless overridden in subclasses, the string prefix of every map is "Map".

    definition classes: MapLikeTraversableLike
  129. def sum: Int

    [use case] Sums up the elements of this collection .

    [use case]

    Sums up the elements of this collection .

    returns

    the sum of all elements in this map 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 map and as result type of sum. Examples of such types are: Long, Float, Double, BigInt.

    attributes: abstract
  130. def sum[B >: (A, B)](implicit num: Numeric[B]): B

    Sums up the elements of this collection .

    Sums up the elements of this collection .

    B

    the result type of the + operator.

    num

    an implicit parameter defining a set of numeric operations which includes the + operator to be used in forming the sum.

    returns

    the sum of all elements of this map with respect to the + operator in num.

    definition classes: TraversableOnce
  131. def synchronized[T0](arg0: T0): T0

    attributes: final
    definition classes: AnyRef
  132. def tail: Map[A, B]

    Selects all elements except the first .

    Selects all elements except the first .

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    returns

    a map consisting of all elements of this map except the first one .

    definition classes: TraversableLike
  133. def take(n: Int): Map[A, B]

    Selects first n elements.

    Selects first n elements.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    n

    Tt number of elements to take from this map .

    returns

    a map consisting only of the first n elements of this map, or else the whole map, if it has less than n elements.

    definition classes: IterableLikeTraversableLike
  134. def takeRight(n: Int): Map[A, B]

    Selects last n elements.

    Selects last n elements.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    n

    the number of elements to take

    returns

    a map consisting only of the last n elements of this map, or else the whole map, if it has less than n elements.

    definition classes: IterableLike
  135. def takeWhile(p: ((A, B)) ⇒ Boolean): Map[A, B]

    Takes longest prefix of elements that satisfy a predicate .

    Takes longest prefix of elements that satisfy a predicate .

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    p

    The predicate used to test elements .

    returns

    the longest prefix of this map whose elements all satisfy the predicate p.

    definition classes: IterableLikeTraversableLike
  136. def thisCollection: Iterable[(A, B)]

    The underlying collection seen as an instance of Map.

    The underlying collection seen as an instance of Map. By default this is implemented as the current collection object itself, but this can be overridden.

    attributes: protected[this]
    definition classes: IterableLikeTraversableLike
  137. def toArray: Array[(A, B)]

    [use case] Converts this map to an array .

    [use case]

    Converts this map to an array .

    returns

    an array containing all elements of this map. A ClassManifest must be available for the element type of this map.

    attributes: abstract
  138. def toArray[B >: (A, B)](implicit arg0: ClassManifest[B]): Array[B]

    Converts this map to an array .

    Converts this map to an array .

    B

    the type of the elements of the array. A ClassManifest for this type must be available.

    returns

    an array containing all elements of this map .

    definition classes: TraversableOnce
  139. def toCollection(repr: Map[A, B]): Iterable[(A, B)]

    A conversion from collections of type Repr to Map objects.

    A conversion from collections of type Repr to Map objects. By default this is implemented as just a cast, but this can be overridden.

    attributes: protected[this]
    definition classes: IterableLikeTraversableLike
  140. def toIndexedSeq[B >: (A, B)]: IndexedSeq[B]

    Converts this map to an indexed sequence .

    Converts this map to an indexed sequence .

    returns

    an indexed sequence containing all elements of this map .

    definition classes: TraversableOnce
  141. def toIterable: Iterable[(A, B)]

    Converts this map to an iterable collection .

    Converts this map to an iterable collection .

    returns

    an Iterable containing all elements of this map.

    definition classes: IterableLikeTraversableOnce
  142. def toIterator: Iterator[(A, B)]

    Returns an Iterator over the elements in this map .

    Returns an Iterator over the elements in this map . Will return the same Iterator if this instance is already an Iterator.

    returns

    an Iterator containing all elements of this map .

    definition classes: TraversableLikeTraversableOnce
  143. def toList: List[(A, B)]

    Converts this map to a list .

    Converts this map to a list .

    returns

    a list containing all elements of this map .

    definition classes: TraversableOnce
  144. def toMap[T, U](implicit ev: <:<[(A, B), (T, U)]): Map[T, U]

    Converts this map to a map .

    Converts this map to a map . This method is unavailable unless the elements are members of Tuple2, each ((K, V)) 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.

    returns

    a map containing all elements of this map .

    definition classes: TraversableOnce
  145. def toSeq: Seq[(A, B)]

    Converts this map to a sequence .

    Converts this map to a sequence .

    returns

    a sequence containing all elements of this map .

    definition classes: TraversableOnce
  146. def toSet[B >: (A, B)]: Set[B]

    Converts this map to a set .

    Converts this map to a set .

    returns

    a set containing all elements of this map .

    definition classes: TraversableOnce
  147. def toStream: Stream[(A, B)]

    Converts this map to a stream .

    Converts this map to a stream .

    returns

    a stream containing all elements of this map .

    definition classes: IterableLikeTraversableOnce
  148. def toString(): String

    Converts this map to a string .

    Converts this map to a string .

    returns

    a string representation of this collection. By default this string consists of the stringPrefix of this map, followed by all elements separated by commas and enclosed in parentheses.

    definition classes: MapLikeTraversableLikeFunction1 → AnyRef → Any
  149. def toTraversable: Traversable[(A, B)]

    Converts this map to an unspecified Traversable .

    Converts this map to an unspecified Traversable . Will return the same collection if this instance is already Traversable.

    returns

    a Traversable containing all elements of this map .

    definition classes: TraversableLikeTraversableOnce
  150. def transpose[B](implicit asTraversable: ((A, B)) ⇒ Traversable[B]): Iterable[Iterable[B]]

    Transposes this map of traversable collections into a map of maps .

    Transposes this map of traversable collections into a map of maps .

    B

    the type of the elements of each traversable collection .

    asTraversable

    an implicit conversion which asserts that the element type of this map is a Traversable.

    returns

    a two-dimensional map of maps which has as nth row the nth column of this map.

    definition classes: GenericTraversableTemplate
  151. def unzip[A1, A2](implicit asPair: ((A, B)) ⇒ (A1, A2)): (Iterable[A1], Iterable[A2])

    Converts this map of pairs into two collections of the first and second halfs of each pair .

    Converts this map of pairs into two collections of the first and second halfs of each pair .

    asPair

    an implicit conversion which asserts that the element type of this map is a pair .

    returns

    a pair maps, containing the first, respectively second half of each element pair of this map .

    definition classes: GenericTraversableTemplate
  152. def updated(key: A, value: B): Map[A, B]

    [use case] Creates a new map obtained by updating this map with a given key/value pair .

    [use case]

    Creates a new map obtained by updating this map with a given key/value pair .

    key

    the key

    value

    the value

    returns

    A new map with the new key/value mapping added to this map .

    attributes: abstract
  153. def updated[B1 >: B](key: A, value: B1): Map[A, B1]

    Creates a new map obtained by updating this map with a given key/value pair .

    Creates a new map obtained by updating this map with a given key/value pair .

    B1

    the type of the added value

    key

    the key

    value

    the value

    returns

    A new map with the new key/value mapping added to this map .

    definition classes: MapLike
  154. def values: Iterable[B]

    Collects all values of this map in an iterable collection .

    Collects all values of this map in an iterable collection .

    returns

    the values of this map as an iterable .

    definition classes: MapLike
  155. def valuesIterator: Iterator[B]

    Creates an iterator for all values in this map .

    Creates an iterator for all values in this map .

    returns

    an iterator over all values that are associated with some key in this map .

    definition classes: MapLike
  156. def view(from: Int, until: Int): IterableView[(A, B), Map[A, B]]

    Creates a non-strict view of a slice of this map .

    Creates a non-strict view of a slice of this map .

    Note: the difference between view and slice is that view produces a view of the current map, whereas slice produces a new map.

    Note: view(from, to) is equivalent to view.slice(from, to)

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    from

    the index of the first element of the view

    until

    the index of the element following the view

    returns

    a non-strict view of a slice of this map, starting at index from and extending up to (but not including) index until.

    definition classes: IterableLikeTraversableLike
  157. def view: IterableView[(A, B), Map[A, B]]

    Creates a non-strict view of this map .

    Creates a non-strict view of this map .

    returns

    a non-strict view of this map .

    definition classes: IterableLikeTraversableLike
  158. def wait(): Unit

    attributes: final
    definition classes: AnyRef
  159. def wait(arg0: Long, arg1: Int): Unit

    attributes: final
    definition classes: AnyRef
  160. def wait(arg0: Long): Unit

    attributes: final
    definition classes: AnyRef
  161. def withFilter(p: ((A, B)) ⇒ Boolean): WithFilter

    Creates a non-strict filter of this map .

    Creates a non-strict filter of this map .

    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.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    p

    the predicate used to test elements .

    returns

    an object of class WithFilter, which supports map, flatMap, foreach, and withFilter operations. All these operations apply to those elements of this map which satisfy the predicate p.

    definition classes: TraversableLike
  162. def zip[B](that: Iterable[B]): Map[((A, B), B)]

    [use case] Returns a map formed from this map and another iterable collection by combining corresponding elements in pairs .

    [use case]

    Returns a map formed from this map and another iterable collection by combining corresponding elements in pairs . If one of the two collections is longer than the other, its remaining elements are ignored.

    B

    the type of the second half of the returned pairs

    that

    The iterable providing the second half of each result pair

    returns

    a new map containing pairs consisting of corresponding elements of this map and that. The length of the returned collection is the minimum of the lengths of this map and that.

    attributes: abstract
  163. def zip[A1 >: (A, B), B, That](that: Iterable[B])(implicit bf: CanBuildFrom[Map[A, B], (A1, B), That]): That

    Returns a map formed from this map and another iterable collection by combining corresponding elements in pairs .

    Returns a map formed from this map and another iterable collection by combining corresponding elements in pairs . If one of the two collections is longer than the other, its remaining elements are ignored.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    A1

    the type of the first half of the returned pairs (this is always a supertype of the collection's element type A).

    B

    the type of the second half of the returned pairs

    That

    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 (A1, B) being admissible for that class, which means that an implicit instance of type CanBuildFrom[Repr, (A1, B), That]. is found.

    that

    The iterable providing the second half of each result pair

    bf

    an implicit value of class CanBuildFrom which determines the result class That from the current representation type Repr and the new element type (A1, B).

    returns

    a new collection of type That containing pairs consisting of corresponding elements of this map and that. The length of the returned collection is the minimum of the lengths of this map and that.

    definition classes: IterableLike
  164. def zipAll[B](that: Iterable[B], thisElem: (A, B), thatElem: B): Map[((A, B), B)]

    [use case] Returns a map formed from this map and another iterable collection by combining corresponding elements in pairs .

    [use case]

    Returns a map formed from this map and another iterable collection by combining corresponding elements in pairs . If one of the two collections is shorter than the other, placeholder elements are used to extend the shorter collection to the length of the longer.

    B

    the type of the second half of the returned pairs

    that

    The iterable providing the second half of each result pair

    thisElem

    the element to be used to fill up the result if this map is shorter than that.

    thatElem

    the element to be used to fill up the result if that is shorter than this map.

    returns

    a new map containing pairs consisting of corresponding elements of this map and that. The length of the returned collection is the maximum of the lengths of this map and that. If this map is shorter than that, thisElem values are used to pad the result. If that is shorter than this map, thatElem values are used to pad the result.

    attributes: abstract
  165. def zipAll[B, A1 >: (A, B), That](that: Iterable[B], thisElem: A1, thatElem: B)(implicit bf: CanBuildFrom[Map[A, B], (A1, B), That]): That

    Returns a map formed from this map and another iterable collection by combining corresponding elements in pairs .

    Returns a map formed from this map and another iterable collection by combining corresponding elements in pairs . If one of the two collections is shorter than the other, placeholder elements are used to extend the shorter collection to the length of the longer.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    that

    the iterable providing the second half of each result pair

    thisElem

    the element to be used to fill up the result if this map is shorter than that.

    thatElem

    the element to be used to fill up the result if that is shorter than this map.

    returns

    a new collection of type That containing pairs consisting of corresponding elements of this map and that. The length of the returned collection is the maximum of the lengths of this map and that. If this map is shorter than that, thisElem values are used to pad the result. If that is shorter than this map, thatElem values are used to pad the result.

    definition classes: IterableLike
  166. def zipWithIndex: Map[((A, B), Int)]

    [use case] Zips this map with its indices .

    [use case]

    Zips this map with its indices .

    returns

    A new map containing pairs consisting of all elements of this map paired with their index. Indices start at 0. @example List("a", "b", "c").zipWithIndex = List(("a", 0), ("b", 1), ("c", 2))

    attributes: abstract
  167. def zipWithIndex[A1 >: (A, B), That](implicit bf: CanBuildFrom[Map[A, B], (A1, Int), That]): That

    Zips this map with its indices .

    Zips this map with its indices .

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    A1

    the type of the first half of the returned pairs (this is always a supertype of the collection's element type A).

    That

    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 (A1, Int) being admissible for that class, which means that an implicit instance of type CanBuildFrom[Repr, (A1, Int), That]. is found.

    returns

    A new collection of type That containing pairs consisting of all elements of this map paired with their index. Indices start at 0.

    definition classes: IterableLike