# MultiMap

#### trait MultiMap [A, B] extends Map[A, Set[B]]

A trait for mutable maps with multiple values assigned to a key.

This class is typically used as a mixin. It turns maps which map `A` to `Set[B]` objects into multi maps which map `A` to `B` objects.

linear super types: Map[A, Set[B]], MapLike[A, Set[B], Map[A, Set[B]]], Cloneable[Map[A, Set[B]]], Shrinkable[A], Builder[(A, Set[B]), Map[A, Set[B]]], Growable[(A, Set[B])], Map[A, Set[B]], MapLike[A, Set[B], Map[A, Set[B]]], Subtractable[A, Map[A, Set[B]]], PartialFunction[A, Set[B]], (A) ⇒ Set[B], Iterable[(A, Set[B])], Iterable[(A, Set[B])], IterableLike[(A, Set[B]), Map[A, Set[B]]], Equals, Traversable[(A, Set[B])], Mutable, Traversable[(A, Set[B])], GenericTraversableTemplate[(A, Set[B]), Iterable], TraversableLike[(A, Set[B]), Map[A, Set[B]]], TraversableOnce[(A, Set[B])], FilterMonadic[(A, Set[B]), Map[A, Set[B]]], HasNewBuilder[(A, Set[B]), Map[A, Set[B]]], AnyRef, Any
source: MultiMap.scala
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1. MultiMap
2. Map
3. MapLike
4. Cloneable
5. Shrinkable
6. Builder
7. Growable
8. Map
9. MapLike
10. Subtractable
11. PartialFunction
12. Function1
13. Iterable
14. Iterable
15. IterableLike
16. Equals
17. Traversable
18. Mutable
19. Traversable
20. GenericTraversableTemplate
21. TraversableLike
22. TraversableOnce
24. HasNewBuilder
25. AnyRef
26. Any
Visibility
1. Public
2. All
Impl.
1. Concrete
2. Abstract

### 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, Set[B]]

The type implementing this traversable

The type implementing this traversable

attributes: protected
definition classes: TraversableLike
4. #### class WithFilter extends FilterMonadic[A, Repr]

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 + [B1 >: B] (elem1: (A, B1), elem2: (A, B1), elems: (A, B1)*) : Map[A, B1]

Creates a new map containing two or more key/value mappings and all the key/value mappings of this map.

Creates a new map containing two or more key/value mappings and all the key/value mappings of this map.

Specified mappings will override existing mappings from this map with the same keys.

B1

the type of the added values

elem1

elem2

elems

returns

a new map containing mappings of this map and two or more specified mappings.

definition classes: MapLikeMapLike
7. #### def + [B1 >: B] (kv: (A, B1)) : Map[A, B1]

Creates a new map containing a new key/value mapping and all the key/value mappings of this map.

Creates a new map containing a new key/value mapping and all the key/value mappings of this map.

Mapping `kv` will override existing mappings from this map with the same key.

B1

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

kv

the key/value mapping to be added

returns

a new map containing mappings of this map and the mapping `kv`.

definition classes: MapLikeMapLike
8. #### def ++ [B1 >: B] (xs: TraversableOnce[(A, B1)]) : Map[A, B1]

Creates a new map containing the key/value mappings provided by the specified traversable object and all the key/value mappings of this map.

Creates a new map containing the key/value mappings provided by the specified traversable object and all the key/value mappings of this map.

Note that existing mappings from this map with the same key as those in `xs` will be overriden.

B1

the type of the added values

xs

the traversable object.

returns

a new map containing mappings of this map and those provided by `xs`.

definition classes: MapLikeMapLike
9. #### def ++ (that: TraversableOnce[(A, Set[B])]) : MultiMap[(A, Set[B])]

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

[use case]

Concatenates this multimap with the elements of a traversable collection.

that

the traversable to append.

returns

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

attributes: abstract
definition classes: TraversableLike
10. #### def ++ [B >: A, That] (that: TraversableOnce[B])(implicit bf: CanBuildFrom[Map[A, Set[B]], B, That]) : That

Concatenates this multimap with the elements of a traversable collection.

Concatenates this multimap 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 multimap followed by all elements of `that`.

definition classes: TraversableLike
11. #### def ++= (xs: TraversableOnce[(A, Set[B])]) : MultiMap.this.type

adds all elements produced by a TraversableOnce to this multimap.

adds all elements produced by a TraversableOnce to this multimap.

returns

the multimap itself.

definition classes: Growable
12. #### def += (elem1: (A, Set[B]), elem2: (A, Set[B]), elems: (A, Set[B])*) : MultiMap.this.type

adds two or more elements to this multimap.

adds two or more elements to this multimap.

elem1

elem2

elems

returns

the multimap itself

definition classes: Growable
13. #### def += (kv: (A, Set[B])) : MultiMap.this.type

Adds a new key/value pair to this map.

Adds a new key/value pair to this map. If the map already contains a mapping for the key, it will be overridden by the new value.

kv

the key/value pair.

returns

the map itself

attributes: abstract
definition classes: MapLikeBuilderGrowable
14. #### def - (elem1: A, elem2: A, elems: A*) : Map[A, Set[B]]

Creates a new map with all the key/value mappings of this map except mappings with keys equal to any of the two or more specified keys.

Creates a new map with all the key/value mappings of this map except mappings with keys equal to any of the two or more specified keys.

elem1

the first element to remove.

elem2

the second element to remove.

elems

the remaining elements to remove.

returns

a new map containing all the mappings of this map except mappings with a key equal to `elem1`, `elem2` or any of `elems`.

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

Creates a new map with all the key/value mappings of this map except the key/value mapping with the specified key.

Creates a new map with all the key/value mappings of this map except the key/value mapping with the specified key.

key

the key to be removed

returns

a new map with all the mappings of this map except that with a key `key`.

definition classes: MapLikeMapLikeSubtractable
16. #### def -- (xs: TraversableOnce[A]) : Map[A, Set[B]]

Creates a new map with all the key/value mappings of this map except mappings with keys equal to any of those provided by the specified traversable object.

Creates a new map with all the key/value mappings of this map except mappings with keys equal to any of those provided by the specified traversable object.

xs

the traversable object.

returns

a new map with all the key/value mappings of this map except mappings with a key equal to a key from `xs`.

definition classes: MapLikeSubtractable
17. #### def --= (xs: TraversableOnce[A]) : MultiMap.this.type

Removes all elements produced by an iterator from this multimap.

Removes all elements produced by an iterator from this multimap.

returns

the multimap itself

definition classes: Shrinkable
18. #### def -= (elem1: A, elem2: A, elems: A*) : MultiMap.this.type

Removes two or more elements from this multimap.

Removes two or more elements from this multimap.

elem1

the first element to remove.

elem2

the second element to remove.

elems

the remaining elements to remove.

returns

the multimap itself

definition classes: Shrinkable
19. #### def -= (key: A) : MultiMap.this.type

Removes a key from this map.

Removes a key from this map.

key

the key to be removed

returns

the map itself.

attributes: abstract
definition classes: MapLikeShrinkable
20. #### def /: [B] (z: B)(op: (B, (A, Set[B])) ⇒ B) : B

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

Applies a binary operator to a start value and all elements of this multimap, 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 multimap, 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 multimap.

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

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

Applies a binary operator to all elements of this multimap 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 multimap, 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 multimap.

definition classes: TraversableOnce
22. #### 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
23. #### 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
24. #### def add (key: A, value: B) : MultiMap.this.type

deprecated:

25. #### def addBinding (key: A, value: B) : MultiMap.this.type

Assigns the specified `value` to a specified `key`, replacing the existing value assigned to that `key` if it is equal to the specified value.

Assigns the specified `value` to a specified `key`, replacing the existing value assigned to that `key` if it is equal to the specified value. Otherwise, simply adds another binding to the `key`.

key

The key to which to bind the new value.

value

The value to bind to the key.

returns

A reference to this multimap.

26. #### 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
27. #### def addString (b: StringBuilder) : StringBuilder

Appends all elements of this multimap to a string builder.

Appends all elements of this multimap to a string builder. The written text consists of the string representations (w.r.t. the method `toString`) of all elements of this multimap 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
28. #### def addString (b: StringBuilder, sep: String) : StringBuilder

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

Appends all elements of this multimap 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 multimap, 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
29. #### def andThen [C] (k: (Set[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
30. #### def apply (key: A) : Set[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
31. #### 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 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 typed.

returns

attributes: final
definition classes: Any
32. #### 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 multimap should be compared

returns

`true`, if this multimap 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
33. #### def clear () : Unit

Removes all bindings from the map.

Removes all bindings from the map. After this operation has completed, the map will be empty.

definition classes: MapLikeBuilderGrowable
34. #### def clone () : Map[A, Set[B]]

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.

definition classes: MapLikeCloneable → AnyRef
35. #### def collect [B] (pf: PartialFunction[(A, Set[B]), B]) : MultiMap[B]

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

[use case]

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

B

the element type of the returned collection.

pf

the partial function which filters and maps the multimap.

returns

a new multimap 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
definition classes: TraversableLike
36. #### def collect [B, That] (pf: PartialFunction[(A, Set[B]), B])(implicit bf: CanBuildFrom[Map[A, Set[B]], B, That]) : That

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

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

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
37. #### def companion : GenericCompanion[Iterable]

The factory companion object that builds instances of class MultiMap

The factory companion object that builds instances of class MultiMap

version
1. 2.8

since
1. 1 is not a `Seq`.)

38. #### def compose [A] (g: (A) ⇒ A) : (A) ⇒ Set[B]

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

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

definition classes: Function1
39. #### 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
40. #### def copyToArray (xs: Array[(A, Set[B])], start: Int, len: Int) : Unit

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

[use case]

Copies elements of this multimap to an array. Fills the given array `xs` with at most `len` elements of this multimap, starting at position `start`. Copying will stop once either the end of the current multimap 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
definition classes: TraversableLike
41. #### def copyToArray [B >: A] (xs: Array[B], start: Int, len: Int) : Unit

Copies elements of this multimap to an array.

Copies elements of this multimap to an array. Fills the given array `xs` with at most `len` elements of this multimap, starting at position `start`. Copying will stop once either the end of the current multimap 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
42. #### def copyToArray (xs: Array[(A, Set[B])]) : Unit

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

[use case]

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

xs

the array to fill.

attributes: abstract
definition classes: TraversableOnce
43. #### def copyToArray [B >: A] (xs: Array[B]) : Unit

Copies values of this multimap to an array.

Copies values of this multimap to an array. Fills the given array `xs` with values of this multimap. Copying will stop once either the end of the current multimap 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
44. #### def copyToArray (xs: Array[(A, Set[B])], start: Int) : Unit

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

[use case]

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

xs

the array to fill.

start

the starting index.

attributes: abstract
definition classes: TraversableOnce
45. #### def copyToArray [B >: A] (xs: Array[B], start: Int) : Unit

Copies values of this multimap to an array.

Copies values of this multimap to an array. Fills the given array `xs` with values of this multimap, after skipping `start` values. Copying will stop once either the end of the current multimap 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
46. #### def copyToBuffer [B >: A] (dest: Buffer[B]) : Unit

Copies all elements of this multimap to a buffer.

Copies all elements of this multimap to a buffer.

dest

The buffer to which elements are copied.

definition classes: TraversableOnce
47. #### def count (p: ((A, Set[B])) ⇒ Boolean) : Int

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

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

p

the predicate used to test elements.

returns

the number of elements satisfying the predicate `p`.

definition classes: TraversableOnce
48. #### def default (key: A) : Set[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
49. #### def drop (n: Int) : Map[A, Set[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 multimap.

returns

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

definition classes: TraversableLike
50. #### def dropRight (n: Int) : Map[A, Set[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 multimap consisting of all elements of this multimap except the first `n` ones, or else the empty multimap, if this multimap has less than `n` elements.

definition classes: IterableLike
51. #### def dropWhile (p: ((A, Set[B])) ⇒ Boolean) : Map[A, Set[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 multimap whose first element does not satisfy the predicate `p`.

definition classes: TraversableLike
52. #### def elements : Iterator[(A, Set[B])]

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

53. #### def empty : Map[A, Set[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: MapMapMapLike
54. #### def entryExists (key: A, p: (B) ⇒ Boolean) : Boolean

Checks if there exists a binding to `key` such that it satisfies the predicate `p`.

Checks if there exists a binding to `key` such that it satisfies the predicate `p`.

key

The key for which the predicate is checked.

p

The predicate which a value assigned to the key must satisfy.

returns

A boolean if such a binding exists

55. #### 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
56. #### 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
57. #### def exists (p: ((A, Set[B])) ⇒ Boolean) : Boolean

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

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

p

the predicate used to test elements.

returns

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

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

Selects all elements of this multimap which satisfy a predicate.

Selects all elements of this multimap which satisfy a predicate.

p

the predicate used to test elements.

returns

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

definition classes: TraversableLike
59. #### def filterKeys (p: (A) ⇒ Boolean) : Map[A, Set[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
60. #### def filterNot (p: ((A, Set[B])) ⇒ Boolean) : Map[A, Set[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
61. #### 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 `finalize`and non-local returns and exceptions, are all platform dependent.

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

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

Finds the first element of the multimap 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 multimap that satisfies `p`, or `None` if none exists.

definition classes: IterableLikeTraversableLikeTraversableOnce
63. #### def first : (A, Set[B])

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

64. #### def firstOption : Option[(A, Set[B])]

`None` if iterable is empty.

`None` if iterable is empty.

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

65. #### def flatMap [B] (f: ((A, Set[B])) ⇒ Traversable[B]) : MultiMap[B]

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

[use case]

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

B

the element type of the returned collection.

f

the function to apply to each element.

returns

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

attributes: abstract
definition classes: TraversableLike
66. #### def flatMap [B, That] (f: ((A, Set[B])) ⇒ Traversable[B])(implicit bf: CanBuildFrom[Map[A, Set[B]], B, That]) : That

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

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

67. #### def flatten [B] : MultiMap[B]

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

[use case]

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

B

the type of the elements of each traversable collection.

returns

a new multimap resulting from concatenating all element multimaps.

attributes: abstract
definition classes: GenericTraversableTemplate
68. #### def flatten [B] (implicit asTraversable: ((A, Set[B])) ⇒ Traversable[B]) : Iterable[B]

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

Converts this multimap of traversable collections into a multimap 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 multimap is a `Traversable`.

returns

a new multimap resulting from concatenating all element multimaps.

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

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

Applies a binary operator to a start value and all elements of this multimap, 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 multimap, 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 multimap.

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

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

Applies a binary operator to all elements of this multimap 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 multimap, 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 multimap.

definition classes: IterableLikeTraversableOnce
71. #### def forall (p: ((A, Set[B])) ⇒ Boolean) : Boolean

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

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

p

the predicate used to test elements.

returns

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

definition classes: IterableLikeTraversableLikeTraversableOnce
72. #### def foreach (f: ((A, Set[B])) ⇒ Unit) : Unit

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

[use case]

Applies a function `f` to all elements of this multimap.

f

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

attributes: abstract
definition classes: IterableLike
73. #### def foreach [U] (f: ((A, Set[B])) ⇒ U) : Unit

Applies a function `f` to all elements of this multimap.

Applies a function `f` to all elements of this multimap.

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.

74. #### def genericBuilder [B] : Builder[B, Iterable[B]]

The generic builder that builds instances of MultiMap

The generic builder that builds instances of MultiMap

definition classes: GenericTraversableTemplate
version
1. 2.8

since
1. 1 at arbitrary element types.

75. #### def get (key: A) : Option[Set[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
76. #### 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
77. #### def getOrElse (key: A, default: ⇒ Set[B]) : Set[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
definition classes: MapLike
78. #### 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
79. #### def getOrElseUpdate (key: A, op: ⇒ Set[B]) : Set[B]

If given key is already in this map, returns associated value.

If given key is already in this map, returns associated value.

Otherwise, computes value from given expression `op`, stores with key in map and returns that value.

key

the key to test

op

the computation yielding the value to associate with `key`, if `key` is previously unbound.

returns

the value associated with key (either previously or as a result of executing the method).

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

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

Partitions this multimap into a map of multimaps 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 multimap.

K

the type of keys returned by the discriminator function.

f

the discriminator function.

returns

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

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

Partitions elements in fixed size multimaps.

Partitions elements in fixed size multimaps.

size

the number of elements per group

returns

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

definition classes: IterableLike
1. Iterator#grouped

82. #### def hasDefiniteSize : Boolean

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

Tests whether this multimap 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
83. #### 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
84. #### def head : (A, Set[B])

Selects the first element of this multimap.

Selects the first element of this multimap.

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

returns

the first element of this multimap.

definition classes: IterableLikeTraversableLike
85. #### def headOption : Option[(A, Set[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 multimap if it is nonempty, `None` if it is empty.

definition classes: TraversableLike
86. #### def init : Map[A, Set[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 multimap consisting of all elements of this multimap except the last one.

definition classes: TraversableLike
87. #### 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
88. #### 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
89. #### 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 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 requested typed.

returns

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

attributes: final
definition classes: Any
90. #### def isTraversableAgain : Boolean

Tests whether this multimap can be repeatedly traversed.

Tests whether this multimap can be repeatedly traversed.

returns

`true`

attributes: final
definition classes: TraversableLikeTraversableOnce
91. #### def iterator : Iterator[(A, Set[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
92. #### 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
93. #### 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
94. #### 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
95. #### def last : (A, Set[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 last element of this multimap.

definition classes: TraversableLike
96. #### def lastOption : Option[(A, Set[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 multimap\$ if it is nonempty, `None` if it is empty.

definition classes: TraversableLike
97. #### def lift : (A) ⇒ Option[Set[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
98. #### def makeSet : Set[B]

Creates a new set.

Creates a new set.

Classes that use this trait as a mixin can override this method to have the desired implementation of sets assigned to new keys. By default this is `HashSet`.

returns

An empty set of values of type `B`.

attributes: protected
99. #### def map [B] (f: ((A, Set[B])) ⇒ B) : MultiMap[B]

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

[use case]

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

B

the element type of the returned collection.

f

the function to apply to each element.

returns

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

attributes: abstract
definition classes: TraversableLike
100. #### def map [B, That] (f: ((A, Set[B])) ⇒ B)(implicit bf: CanBuildFrom[Map[A, Set[B]], B, That]) : That

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

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

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 multimap and collecting the results.

101. #### def mapElements [C] (f: (Set[B]) ⇒ C) : Map[A, C]

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

102. #### def mapResult [NewTo] (f: (Map[A, Set[B]]) ⇒ NewTo) : Builder[(A, Set[B]), NewTo]

Creates a new builder by applying a transformation function to the results of this builder.

Creates a new builder by applying a transformation function to the results of this builder.

NewTo

the type of collection returned by `f`.

f

the transformation function.

returns

a new builder which is the same as the current builder except that a transformation function is applied to this builder's result.

definition classes: Builder
103. #### def mapValues [C] (f: (Set[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
104. #### def max : (A, Set[B])

[use case] Finds the largest element.

[use case]

Finds the largest element.

returns

the largest element of this multimap.

attributes: abstract
definition classes: TraversableOnce
105. #### def max [B >: A] (implicit cmp: Ordering[B]) : (A, Set[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 multimap with respect to the ordering `cmp`.

definition classes: TraversableOnce
106. #### def min : (A, Set[B])

[use case] Finds the smallest element.

[use case]

Finds the smallest element.

returns

the smallest element of this multimap

attributes: abstract
definition classes: TraversableOnce
107. #### def min [B >: A] (implicit cmp: Ordering[B]) : (A, Set[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 multimap with respect to the ordering `cmp`.

definition classes: TraversableOnce
108. #### def mkString : String

Displays all elements of this multimap in a string.

Displays all elements of this multimap in a string.

returns

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

definition classes: TraversableOnce
109. #### def mkString (sep: String) : String

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

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

sep

the separator string.

returns

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

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

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

Displays all elements of this multimap 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 multimap. 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 multimap are separated by the string `sep`.

definition classes: TraversableOnce
111. #### 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
112. #### def newBuilder : Builder[(A, Set[B]), Map[A, Set[B]]]

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

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

Overrides `MapLike` implementation for better efficiency.

attributes: protected[this]
definition classes: MapLikeMapLikeTraversableLikeHasNewBuilder
113. #### def nonEmpty : Boolean

Tests whether the multimap is not empty.

Tests whether the multimap is not empty.

returns

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

definition classes: TraversableOnce
114. #### 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
115. #### 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
116. #### 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
117. #### def partition (p: ((A, Set[B])) ⇒ Boolean) : (Map[A, Set[B]], Map[A, Set[B]])

Partitions this multimap in two multimaps according to a predicate.

Partitions this multimap in two multimaps according to a predicate.

p

the predicate on which to partition.

returns

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

definition classes: TraversableLike
118. #### def product : (A, Set[B])

[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 multimap 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 multimap and as result type of `product`. Examples of such types are: `Long`, `Float`, `Double`, `BigInt`.

attributes: abstract
definition classes: TraversableOnce
119. #### def product [B >: A] (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 multimap with respect to the `*` operator in `num`.

definition classes: TraversableOnce
120. #### def projection : IterableView[(A, Set[B]), Map[A, Set[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`

121. #### def put (key: A, value: Set[B]) : Option[Set[B]]

Adds a new key/value pair to this map and optionally returns previously bound value.

Adds a new key/value pair to this map and optionally returns previously bound value. If the map already contains a mapping for the key, it will be overridden by the new value.

key

the key to update

value

the new value

returns

an option value containing the value associated with the key before the `put` operation was executed, or `None` if `key` was not defined in the map before.

definition classes: MapLike
122. #### def reduceLeft [B >: A] (op: (B, (A, Set[B])) ⇒ B) : B

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

Applies a binary operator to all elements of this multimap, 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 multimap, going left to right: op(...(op(x1, x2), ... ) , xn) where `x,,1,,, ..., x,,n,,` are the elements of this multimap.

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

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

Optionally applies a binary operator to all elements of this multimap, 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 multimap is nonempty, `None` otherwise.

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

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

Applies a binary operator to all elements of this multimap, 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 multimap, going right to left: op(x1, op(x2, ..., op(xn-1, xn)...)) where `x,,1,,, ..., x,,n,,` are the elements of this multimap.

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

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

Optionally applies a binary operator to all elements of this multimap, 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 multimap is nonempty, `None` otherwise.

definition classes: TraversableOnce
126. #### def remove (key: A) : Option[Set[B]]

Removes a key from this map, returning the value associated previously with that key as an option.

Removes a key from this map, returning the value associated previously with that key as an option.

key

the key to be removed

returns

an option value containing the value associated previously with `key`, or `None` if `key` was not defined in the map before.

definition classes: MapLike
127. #### def removeBinding (key: A, value: B) : MultiMap.this.type

Removes the binding of `value` to `key` if it exists.

Removes the binding of `value` to `key` if it exists.

If this was the last value assigned to the specified key, the set assigned to that key will be removed as well.

key

The key of the binding.

value

The value to remove.

returns

A reference to this multimap.

128. #### def removeKey (key: A) : Option[Set[B]]

If given key is defined in this map, remove it and return associated value as an Option.

If given key is defined in this map, remove it and return associated value as an Option. If key is not present return None.

key

the key to be removed

definition classes: MapLike
deprecated:
1. Use `remove' instead`

129. #### def repr : Map[A, Set[B]]

The collection of type multimap underlying this `TraversableLike` object.

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

definition classes: TraversableLike
130. #### def result () : Map[A, Set[B]]

The result when this map is used as a builder

The result when this map is used as a builder

returns

the map representation itself.

definition classes: MapLikeBuilder
131. #### def retain (p: (A, Set[B]) ⇒ Boolean) : MultiMap.this.type

Retains only those mappings for which the predicate `p` returns `true`.

Retains only those mappings for which the predicate `p` returns `true`.

p

The test predicate

definition classes: MapLike
132. #### def reversed : List[(A, Set[B])]

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

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

[use case]

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

that

the collection to compare with.

returns

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

attributes: abstract
definition classes: IterableLike
134. #### def sameElements [B >: A] (that: Iterable[B]) : Boolean

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

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

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
135. #### def scanLeft [B, That] (z: B)(op: (B, (A, Set[B])) ⇒ B)(implicit bf: CanBuildFrom[Map[A, Set[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
136. #### def scanRight [B, That] (z: B)(op: ((A, Set[B]), B) ⇒ B)(implicit bf: CanBuildFrom[Map[A, Set[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
137. #### def size : Int

The size of this multimap.

The size of this multimap.

returns

the number of elements in this multimap.

definition classes: TraversableOnce
138. #### def sizeHint (coll: scala.collection.TraversableLike[_, _], delta: Int =0) : Unit

Gives a hint that one expects the `result` of this builder to have the same size as the given collection, plus some delta.

Gives a hint that one expects the `result` of this builder to have the same size as the given collection, plus some delta. This will provide a hint only if the collection is known to have a cheap `size` method. Currently this is assumed ot be the case if and only if the collection is of type `IndexedSeqLike`. Some builder classes will optimize their representation based on the hint. However, builder implementations are still required to work correctly even if the hint is wrong, i.e. a different number of elements is added.

coll

the collection which serves as a hint for the result's size.

delta

a correction to add to the `coll.size` to produce the size hint.

definition classes: Builder
139. #### def sizeHint (size: Int) : Unit

Gives a hint how many elements are expected to be added when the next `result` is called.

Gives a hint how many elements are expected to be added when the next `result` is called. Some builder classes will optimize their representation based on the hint. However, builder implementations are still required to work correctly even if the hint is wrong, i.e. a different number of elements is added.

size

the hint how many elements will be added.

definition classes: Builder
140. #### def sizeHintBounded (size: Int, boundingColl: scala.collection.TraversableLike[_, _]) : Unit

Gives a hint how many elements are expected to be added when the next `result` is called, together with an upper bound given by the size of some other collection.

Gives a hint how many elements are expected to be added when the next `result` is called, together with an upper bound given by the size of some other collection. Some builder classes will optimize their representation based on the hint. However, builder implementations are still required to work correctly even if the hint is wrong, i.e. a different number of elements is added.

size

the hint how many elements will be added.

boundingColl

the bounding collection. If it is an IndexedSeqLike, then sizes larger than collection's size are reduced.

definition classes: Builder
141. #### def slice (from: Int, until: Int) : Map[A, Set[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 multimap.

until

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

returns

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

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

definition classes: IterableLike
143. #### def sliding [B >: A] (size: Int) : Iterator[Map[A, Set[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 multimaps of size `size`, except the last and the only element will be truncated if there are fewer elements than size.

definition classes: IterableLike
1. Iterator#sliding

144. #### def span (p: ((A, Set[B])) ⇒ Boolean) : (Map[A, Set[B]], Map[A, Set[B]])

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

Splits this multimap 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 multimap whose elements all satisfy `p`, and the rest of this multimap.

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

Splits this multimap into two at a given position.

Splits this multimap 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 multimaps consisting of the first `n` elements of this multimap, and the other elements.

definition classes: TraversableLike
146. #### 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 multimap. Unless overridden in subclasses, the string prefix of every map is `"Map"`.

definition classes: MapLikeTraversableLike
147. #### def sum : (A, Set[B])

[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 multimap 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 multimap and as result type of `sum`. Examples of such types are: `Long`, `Float`, `Double`, `BigInt`.

attributes: abstract
definition classes: TraversableOnce
148. #### def sum [B >: A] (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 multimap with respect to the `+` operator in `num`.

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

attributes: final
definition classes: AnyRef
150. #### def tail : Map[A, Set[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 multimap consisting of all elements of this multimap except the first one.

definition classes: TraversableLike
151. #### def take (n: Int) : Map[A, Set[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 multimap.

returns

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

definition classes: IterableLikeTraversableLike
152. #### def takeRight (n: Int) : Map[A, Set[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 multimap consisting only of the last `n` elements of this multimap, or else the whole multimap, if it has less than `n` elements.

definition classes: IterableLike
153. #### def takeWhile (p: ((A, Set[B])) ⇒ Boolean) : Map[A, Set[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 multimap whose elements all satisfy the predicate `p`.

definition classes: IterableLikeTraversableLike
154. #### def thisCollection : Iterable[(A, Set[B])]

The underlying collection seen as an instance of `MultiMap`

The underlying collection seen as an instance of `MultiMap`

attributes: protected[this]
definition classes: IterableLikeTraversableLike
version
1. 2.8

since
1. 1```. By default this is implemented as the current collection object itself, but this can be overridden. ```

155. #### def toArray : Array[(A, Set[B])]

[use case] Converts this multimap to an array.

[use case]

Converts this multimap to an array.

returns

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

attributes: abstract
definition classes: TraversableOnce
156. #### def toArray [B >: A] (implicit arg0: ClassManifest[B]) : Array[B]

Converts this multimap to an array.

Converts this multimap 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 multimap.

definition classes: TraversableOnce
157. #### def toBuffer [B >: A] : Buffer[B]

Converts this multimap to a mutable buffer.

Converts this multimap to a mutable buffer.

returns

a buffer containing all elements of this multimap.

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

A conversion from collections of type `Repr` to `MultiMap`

A conversion from collections of type `Repr` to `MultiMap`

attributes: protected[this]
definition classes: IterableLikeTraversableLike
version
1. 2.8

since
1. 1``` objects. By default this is implemented as just a cast, but this can be overridden. ```

159. #### def toIndexedSeq [B >: A] : IndexedSeq[B]

Converts this multimap to an indexed sequence.

Converts this multimap to an indexed sequence.

returns

an indexed sequence containing all elements of this multimap.

definition classes: TraversableOnce
160. #### def toIterable : Iterable[(A, Set[B])]

Converts this multimap to an iterable collection.

Converts this multimap 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).

returns

an `Iterable` containing all elements of this multimap.

definition classes: IterableLikeTraversableOnce
161. #### def toIterator : Iterator[(A, Set[B])]

Returns an Iterator over the elements in this multimap.

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

returns

an Iterator containing all elements of this multimap.

definition classes: TraversableLikeTraversableOnce
162. #### def toList : List[(A, Set[B])]

Converts this multimap to a list.

Converts this multimap to a list.

returns

a list containing all elements of this multimap.

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

Converts this multimap to a map.

Converts this multimap 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 multimap.

definition classes: TraversableOnce
164. #### def toSeq : Seq[(A, Set[B])]

Converts this multimap to a sequence.

Converts this multimap to a sequence.

returns

a sequence containing all the elements of this multimap.

definition classes: IterableLikeTraversableOnce
165. #### def toSet [B >: A] : Set[B]

Converts this multimap to a set.

Converts this multimap to a set.

returns

a set containing all elements of this multimap.

definition classes: TraversableOnce
166. #### def toStream : Stream[(A, Set[B])]

Converts this multimap to a stream.

Converts this multimap to a stream.

returns

a stream containing all elements of this multimap.

definition classes: IterableLikeTraversableLikeTraversableOnce
167. #### def toString () : String

Converts this multimap to a string.

Converts this multimap to a string.

returns

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

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

Converts this multimap to an unspecified Traversable.

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

returns

a Traversable containing all elements of this multimap.

definition classes: TraversableLikeTraversableOnce
169. #### def transform (f: (A, Set[B]) ⇒ Set[B]) : MultiMap.this.type

Applies a transformation function to all values contained in this map.

Applies a transformation function to all values contained in this map. The transformation function produces new values from existing keys associated values.

f

the transformation to apply

returns

the map itself.

definition classes: MapLike
170. #### def transpose [B] (implicit asTraversable: ((A, Set[B])) ⇒ Traversable[B]) : Iterable[Iterable[B]]

Transposes this multimap of traversable collections into a multimap of multimaps.

Transposes this multimap of traversable collections into a multimap of multimaps.

B

the type of the elements of each traversable collection.

asTraversable

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

returns

a two-dimensional multimap of multimaps which has as nth row the nth column of this multimap.

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

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

Converts this multimap 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 multimap is a pair.

returns

a pair multimaps, containing the first, respectively second half of each element pair of this multimap.

definition classes: GenericTraversableTemplate
172. #### def update (key: A, value: Set[B]) : Unit

Adds a new key/value pair to this map.

Adds a new key/value pair to this map. If the map already contains a mapping for the key, it will be overridden by the new value.

key

The key to update

value

The new value

definition classes: MapLike
173. #### def updated [B1 >: B] (key: A, value: B1) : Map[A, B1]

Creates a new map consisting of all key/value pairs of the current map plus a new pair of a given key and value.

Creates a new map consisting of all key/value pairs of the current map plus a new pair of a given key and value.

B1

the type of the added value

key

value

The new value

returns

A fresh immutable map with the binding from `key` to `value` added to this map.

definition classes: MapLikeMapLike
174. #### def values : Iterable[Set[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
175. #### def valuesIterator : Iterator[Set[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
176. #### def view (from: Int, until: Int) : IterableView[(A, Set[B]), Map[A, Set[B]]]

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

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

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

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 multimap, starting at index `from` and extending up to (but not including) index `until`.

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

Creates a non-strict view of this multimap.

Creates a non-strict view of this multimap.

returns

a non-strict view of this multimap.

definition classes: IterableLikeTraversableLike
178. #### def wait () : Unit

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

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

attributes: final
definition classes: AnyRef
181. #### def withFilter (p: ((A, Set[B])) ⇒ Boolean) : FilterMonadic[(A, Set[B]), Map[A, Set[B]]]

Creates a non-strict filter of this multimap.

Creates a non-strict filter of this multimap.

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 multimap which satisfy the predicate `p`.

182. #### def zip [B] (that: Iterable[B]) : MultiMap[((A, Set[B]), B)]

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

[use case]

Returns a multimap formed from this multimap 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 multimap containing pairs consisting of corresponding elements of this multimap and `that`. The length of the returned collection is the minimum of the lengths of this multimap and `that`.

attributes: abstract
definition classes: IterableLike
183. #### def zip [A1 >: A, B, That] (that: Iterable[B])(implicit bf: CanBuildFrom[Map[A, Set[B]], (A1, B), That]) : That

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

Returns a multimap formed from this multimap 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 multimap and `that`. The length of the returned collection is the minimum of the lengths of this multimap and `that`.

definition classes: IterableLike
184. #### def zipAll [B] (that: Iterable[B], thisElem: (A, Set[B]), thatElem: B) : MultiMap[((A, Set[B]), B)]

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

[use case]

Returns a multimap formed from this multimap 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 multimap is shorter than `that`.

thatElem

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

returns

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

attributes: abstract
definition classes: IterableLike
185. #### def zipAll [B, A1 >: A, That] (that: Iterable[B], thisElem: A1, thatElem: B)(implicit bf: CanBuildFrom[Map[A, Set[B]], (A1, B), That]) : That

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

Returns a multimap formed from this multimap 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 multimap is shorter than `that`.

thatElem

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

returns

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

definition classes: IterableLike
186. #### def zipWithIndex : MultiMap[((A, Set[B]), Int)]

[use case] Zips this multimap with its indices.

[use case]

Zips this multimap with its indices.

returns

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

attributes: abstract
definition classes: IterableLike
187. #### def zipWithIndex [A1 >: A, That] (implicit bf: CanBuildFrom[Map[A, Set[B]], (A1, Int), That]) : That

Zips this multimap with its indices.

Zips this multimap 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 multimap paired with their index. Indices start at `0`.

definition classes: IterableLike