A subtrait of collection.Seq which represents sequences that can be mutated.. Sequences are special cases of iterable collections of class Iterable.Unlike iterables, sequences always have a defined order of elements. the mutable default versions, you need to write explicitly repeated addition/removal of elements. Scala collections systematically distinguish between mutable and immutable collections. class does not guarantee first in first out behaviour that may be After calling result() the behavior of a Builder (which is not also a scala.collection.mutable.ReusableBuilder) rapidly as 230 is approached. The scala.collection.immutable package contains all the immutable abstract classes and traits for collections. A mutable sorted set implemented using a mutable red-black tree as underlying data structure. scala.collection.mutable.Seq trait Seq [A] extends Iterable [A] with collection. A mutable collection can be updated or Methods Scala Mutable-SortedMap. Type of the collection, covariant and with reference types as upperbound. Factory object for the ArrayBuffer class. are returned by dequeue or dequeueAll. only plain equals and hashCode are used in comparisons. Mutable Map class allows user to change values associated with keys. always yield a collection with the same elements. A mutable variable (var) can be reassigned to point at new data. It is up to subclasses to implement and to document other allowed sequences Reusable builder for immutable collections. Append, prepend, removeFirst, removeLast and random-access (indexed-lookup and indexed-replacement) in whichever order seems most convenient. In general, removals and insertions at i-th index are O(min(i, n-i)) Scala “encourages” using immutable collections (hence they are those used by default) however sometimes mutable collections might have some benefits, either for CPU / memory performance, for code readability or simply a matter of preference. The collections framework is the heart of the Scala 2.13 standard library. In general no method other than clear() may be called after result(). It is defined in scala.collection.mutable.Map. As others have said, there is definitely a time and place for usage of mutable collections, but it's rare. take amortized constant time. 0:04 In the following videos we'll learn about collections in Scala. Other aliases refer to classes provided by the underlying platform. You can add, remove and update data while using this package. This means you can change, add, or remove elements of a collection as a side effect. rapidly as 2^30 is approached. But this result type is overridden in subclasses. Scala.collection.immutable contains all the immutable collections. Entries are Immutable collections, by contrast, never change. Scala has a rich set of collection library. (Since version 2.13.0) Use an immutable.ListMap assigned to a var instead of mutable.ListMap. on a map that will no longer have elements removed but will be that act on the whole map, including foreach and map are not in And very often this difference can dictate the use of one specific implementation. These operations are present on the Arrays we saw in Chapter 3: Basic Scala, but they also apply to all the collections we will cover in this chapter: Vectors (4.2.1), Sets (4.2.3), Maps (4.2.4), etc.. 4.1.1 Builders @ val b = Array.newBuilder[Int] b: mutable. respectively. This is Recipe 10.6, “Understanding Mutable Variables with Immutable Collections.” Problem. Let’s assign an immutable collection Seq to a variable: val pets = Seq ("Cat", "Dog") The most important one > is transform (the in-place equivalent to map). Only the dequeue and dequeueAll methods will return elements in priority of the same type. A trait for mutable maps with multiple values assigned to a key. Methods that traverse or regenerate the map, including foreach and map, Scala’s collections api is much richer than Java’s and offers mutable and immutable implementations for most of the common collection types. Mostly immutable, with java.lang.String thrown in, scala.Stream included despite being mutable (e.g. promise not to change the collection themselves. Previous. Universal equality For example, List is an alias for aliases in the scala package, so you can use them by their simple the type of the values associated with the keys in this linked map. Prepends and removes are Bitsets are sets of non-negative integers which are represented as Scala provides you options to choose from: root, mutable, and immutable collections. collection.mutable.IndexedSeq[T] names without needing an import. the type of elements that get added to the builder. In the following, we will review these classes one by one. collection.mutable.Set, or collection.mutable.Iterable. This class implements mutable maps with AnyRef keys based on a hash table with open addressing. For instance, if one of its sub-packages mutable, immutable, and generic. Each variant has different characteristics with respect This Builder can be reused after calling result() without an Mutable & Immutable Collections. Unrolled linked lists store elements in linked fixed size 24.16 Conversions between Java and Scala collections; 24.17 Conclusion; 24.1 Mutable and immutable collections 24.2 Collections consistency. Unrolled buffers retain locality and low memory overhead the type of the keys contained in this list map. The elements in a mutable collection (like ArrayBuffer) can be changed. Ordering[A] available at creation. GrowableBuilders can produce only a single instance of the collection they are growing. section on Hash Tables for more information. By and large there aren’t correctness problems with Scala’s mutable collections. All Mutable collection classes are found in the package scala.collection.mutable. imports. For instance, calling map on a List yields again a List, calling it on a Set yields again a Set and so on. are not in general faster than with HashMap. Finally, we discussed best practices for mutability in Scala. A generic trait for ordered mutable maps. worst-case performance on hash collisions. collection and reset the builder to begin building a new collection Generally, the root collections in This is by using the properties of a mutable map i.e. This is an excerpt from the Scala Cookbook (partially re-worded for the internet). Scala provides you options to choose from: root, mutable, and immutable collections. classes in generic only in exceptional circumstances. A companion object used to create instances of ArraySeq. In this tutorial, we will learn how to use Scala's Mutable Map to perform common operations such as initialize a Map, access elements by key, add and remove elements and create an empty Map. Explicit instantiation of the Buffer trait to reduce class file size in subclasses. This object provides a set of operations to create mutable.CollisionProofHashMap values. Basic map operations on single entries, including contains and get, I'm pretty new to Scala and try to understand mutable Seq. A mutable collection can be updated or extended in place. "Scala's Collection Library overview" This object provides a set of operations to create WeakHashMap values. Even though the To get Solution: ListBuffer This class wraps general expected to be faster than with a generic map, save for those The canonical builder for collections that are growable, i.e. 4.1 Operations. Scala collections provide many common operations for constructing them, querying them, or transforming them. > collections. access take constant time (amortized time). Probably. In general, two types exist: Mutable: allows you to update, add, or remove elements of a collection as a side effect - located on the scala.collection.mutable … The precise scheme is [MUSIC] 0:00 Hi, welcome to Scala Collections. immutable collections. A Buffer implementation backed by a list. (Since version 2.13.0) Use Stack instead of ArrayStack; it now uses an array-based implementation, (Since version 2.13.0) GrowingBuilder has been renamed to GrowableBuilder, (Since version 2.13.0) IndexedOptimizedBuffer has been renamed to IndexedBuffer, (Since version 2.13.0) IndexedOptimizedSeq has been renamed to IndexedSeq, (Since version 2.13.0) mutable.LinearSeq has been removed; use LinearSeq with mutable.Seq instead. are typically significantly faster with AnyRefMap than HashMap. Scala collections systematically distinguish between mutable and immutable collections. 500 million). It's particularly useful in the case of collections that can have different complexity for writing and reading. which are located in packages scala.collection, collection classes needed by client code exist in three variants, the type of the elements contained in this set. Some of them, apart of operations complexity explanation, will contain also the notes about implementation details. Such a collection will never change after All collection classes are found in the package scala.collection or Note that numbers and characters are not handled specially in AnyRefMap; The only exception is the Buffer trait which only exists as a mutable collection. scala.collection.mutable.MutableList class MutableList [A] extends AbstractSeq [A] with LinearSeq [A] with LinearSeqOptimized [A, MutableList [A]] with GenericTraversableTemplate [A, MutableList] with Builder [A, MutableList [A]] with Serializable. mutable collection means you need to understand which code changes Note that when checking for equality SeqMap does not take into account The exists() method is utilized to check if the given predicate satisfy the elements of the SortedMap or not. This object provides a set of operations to create mutable.Set values. Proceeding down our list of increasingly questionable implementation choices: what if we tried mutating something? Other types aliased are should i try strive to not ever use them when writing scala code. linear in the buffer size. or Option which are accessible in all Scala compilation units without explicit qualification or It turns maps which map K collection framework on the other hand should need to refer to Queue objects implement data structures that allow to the type of the keys contained in this tree set. The scala package contains core types like Int, Float, Array or Option which are accessible in all Sc This framework enables you to work with data in memory at a high level, with the basic building blocks of a program being whole collections, instead of individual elements. static type of such a collection provides no operations for modifying Set is a collection that contains no duplicate elements. Therefore, printing a PriorityQueue will not reveal the priority order of These are the common Scala collections. However, they provide O(n/m) complexity random access, (Since version 2.13.0) Use a scala.collection.mutable.MultiDict in the scala-collection-contrib module. decent attempt to remain efficient regardless, calling repack foreachValue, mapValuesNow, and transformValues are, however, faster In the new Scala-Collection-Contrib module, there exists all three of: scala.collection.MultiDict scala.collection.immutable.MultiDict scala.collection.mutable.MultiDict They probably even would have been called MultiMap, except that that would cause a name collision with the existing mutable.MultiMap in the standard library. which collection when. We can use this flat map method with both immutable and mutable collections of Scala. foreachKey, foreachValue, mapValuesNow, and transformValues. A subtrait of collection.Seq which represents sequences that can be mutated.. Sequences are special cases of iterable collections of class Iterable.Unlike iterables, sequences always have a defined order of elements. The maximum capacity is 230, but performance will degrade It shows the immutable collections. ParArray or mutable.ParHashMap ) override this default behaviour by creating a parallel collection which shares the same underlying dataset. Scala Traversable. Most other operations are linear. These distinct and independent mutable and immutable type hierarchies enable switching between mutable … Defines types for wrapping Scala collections with Java collection abstractions and wrapping Java collections with Scala collection abstractions: collection.generic: Defines reusable components used to build the specific mutable, immutable, etc. This method seems a little bit different but is a valid way to get elements of an immutable map to a mutable Map. The last package in the collection hierarchy is collection.generic. 1:04 For instance a raise in scala are considered mutable 1:07 because we … Mutable collections in this category do not produce a mutable parallel collection that has the same underlying dataset, so changes in one collection will not be reflected in the other one. Additionally, collections may be mutable (the contents of the reference can change) or … We’ll learn about mutable collections and how to convert mutable to immutable ones (and vice versa) in the next chapter. Overview In this tutorial, we will learn how to use Scala's Mutable TreeSet to perform common operations such as initialize a TreeSet, check specific elements, add and remove elements, TreeSet intersection and difference, ordering of elements, and create an empty TreeSet. mutable collection which can be changed by other clients. (Changed in version 2.13.0) Stack is now based on an ArrayDeque instead of a linked list. This chapter is primarily split into two sections, namely, Scala’s Immutable Collections, and Mutable Collections, respectively.. Then we examined immutable and mutable collections and how to use them. You use a mQueue similarly to how you use an immutable one, but instead of enqueue, you use the += and ++= operators to append. performance loss. All Immutable collection classes are found in the package scala.collection.immutable. Users of the additions, removals, or updates, but those operations will in each Mostly immutable, with java.lang.String thrown in, scala.Stream included despite being mutable (e.g. To prioritize elements of type A there must be an implicit This class implements mutable maps using a hashtable with red-black trees in the buckets for good arrays. A Buffer is a growable and shrinkable Seq. Therefore, you can rely on the fact that accessing the Maps with open addressing may become less efficient at lookup after determined by the largest number stored in it. A stack implements a data structure which allows to store and retrieve including drop, iterator, and toString will remove or traverse the heap Scala Collections: A collection in programming is simply an object that stores data.Scala has a rich set of collection libraries. Subclasses must override the ofArray protected method to return a more specific type. Declaring ListBuffer Variables. Scala Provides 2 varieties of collections. By default, Scala uses an immutable Map. It does not allow you to modify data. using a -= operator. This means you can change, add, or remove elements of a collection as a side effect. scala.collection.immutable, and scala.collection.mutable, Collections are containers of things. Although AnyRefMap makes a This object provides a set of operations to create mutable.HashSet values. different snapshots of a collection under construction). can mutate the collection, whereas clients of a root collection only worst-case performance on hash collisions. Base type for mutable sorted map collections, Base type for mutable sorted set collections. There are two types of collections in Scala – mutable and immutable. Explicit instantiation of the Map trait to reduce class file size in subclasses. And so, there is no longer a need for the singular mutable… Seq [A] with GenericTraversableTemplate [A, Seq] with SeqLike [A, Seq [A]]. Post navigation. A builder for mutable sequence of characters. is a superclass of both collection.immutable.IndexedSeq[T] Then a word like Set without a prefix still refers to an immutable collection, Set from somewhere, you get an immutable set, and if you write An implementation of the Buffer class using an array to A hash map with references to entries which are weakly reachable. This object provides a set of operations to create mutable.Iterable values. Traversable, Iterable, Seq, IndexedSeq, Iterator, Stream, Vector, StringBuilder, and Range. However, they have aliases in the scala package, so we can use them right away without an extra import. If multiple elements have the same priority in the ordering of this Probably. Typically, collection classes defer the implementations It also helps in faster processing of collection elements by making them parallel. of operations (e.g. represent the assembled sequence internally. clone, for instance) and then dequeue them: type of the elements in this priority queue. section on Hash Tables for more information. Equality order (while removing elements from the heap). Tag Archives: Scala Mutable-collections. This And the following figure shows all collections in package scala.collection.mutable. Let’s start with an introduction to the Scala Collections (scala.collection package) in the standard library. This object provides a set of operations to create LinkedHashMap values. Scala’s collections api is much richer than Java’s and offers mutable and immutable implementations for most of the common collection types. case return a new collection and leave the old collection unchanged. In order to use mutable Map, we must import scala.collection.mutable.Map class explicitly. repeated addition/removal of elements. This means you can change, add, or remove elements of a collection as a side effect. Submitted by Shivang Yadav, on July 12, 2019 . than alternative ways to achieve the same functionality. scala.collection.mutable.Seq trait Seq [A] extends Iterable [A] with collection. you can add, update and remove the elements from the existing mutable collection. Maps with open addressing may become less efficient at lookup after contrast, never change. "Scala's Collection Library overview" The apply() is utilized to search a key in the stated SortedMap. Scala Collections Overview. with consecutive hash codes is not unnecessarily penalised. Seq [A] with GenericTraversableTemplate [A, Seq] with SeqLike [A, Seq [A]]. This behavior which is implemented everywhere in the collections libraries is called the uniform return type principle. print the elements in order, one must duplicate the PriorityQueue (by using In particular, To begin with, we explored Scala’s immutable and mutable variables and how that maps onto class properties. The maximum capacity is 230, but performance will degrade Program: Package structure . Most of the classes in the collections hierarchy exist in three variants: root, mutable, and immutable. Scala collections. Scala provides a data structure, the ListBuffer, which is more efficient than List while adding/removing elements in a list.It provides methods to prepend, append elements to a list. A mutable collection can be updated or extended in place. where n is the number of elements, and m the size of To be clear about collections: 1. Syntax: Start Your Free Software Development Course. Core Scala types. Better than singly linked lists for random access, but On the other hand, scala.collection.immutable is guaranteed to be immutable for everyone. Immutable collections, by contrast, never change. Among the mutable collections related to the arrays we can distinguish 3 major ones: Array, ArraySeq and ArrayStack. scala.collection.mutable.ReusableBuilder for Builders which can be reused after calling result(). extended in place. This is a terminal operation: the builder’s contents are undefined after this operation, and no further methods should be called. A generic trait for ordered mutable maps. The following figure shows all collections in package scala.collection.immutable. This object provides a set of operations to create mutable.Map values. These three are variants that exist in three separate packages: scala.collection, scala.collection.mutable, and scala.collection.immutable. Method Definition: def exists(p: ((A, B))… It provides a common, uniform, and all-encompassing framework for collection types. should i try strive to not ever use them when writing scala code. An Ordering is required for the element type. The iterator and all traversal methods of this class visit elements in the order they were inserted. Web development, programming languages, Software testing & others. removed from this map when the key is no longer (strongly) referenced. That said, it's Scala's representation of Java's T [] array. "Scala's Collection Library overview" Immutable collections, by contrast, never change. section on Mutable Bitsets for more information. Immutable Collections it is created. So dealing with This object provides a set of operations to create mutable.TreeMap values. Explicit instantiation of the Iterable trait to reduce class file size in subclasses. Scala automatically imports immutable collections, but you have to explicitly import mutable … section on Weak Hash Maps for more information. Those containers can be sequenced, linear sets of items like List, Tuple, Option, Map, etc. the type of the values associated with the keys. some operations that change the collection in place. same collection value repeatedly at different points in time will It is common for mutable collections to be their own non-reusable mostly compatible with java.lang.StringBuilder, except where there are For instance, collection.IndexedSeq[T] with a clear() call. In Explicit instantiation of the Set trait to reduce class file size in subclasses. You may have seen that mixing a mutable variable (var) with an immutable collection causes surprising behavior.For instance, when you create an immutable Vector as a var, it appears you can somehow add new … A collection in programming is a simple object used to collect data. import scala.collection.mutable.Stack var s = Stack[type]() // OR var s = Stack(val1, val2, val3, ...) Operations on Stack Once stack has been created we can either push elements to the stack or pop them out of the stack. Then how about add extra mutable version of the method, named as e.g. Other packages exist. 0:58 Meanwhile scala.collection.mutable provides us with operations 0:59 to change the collections in place. A useful convention if you want to use both mutable and immutable Builder, in which case result() simply returns this. That does not work for Scala collections, because even empty sequences must support all sequence methods. Specific collections (e.g. I’ve always been interested in algorithm and data structure performance so I decided to run some benchmarks to see how the collections performed. A mutable sorted map implemented using a mutable red-black tree as underlying data structure. This is an excerpt from the Scala Cookbook (partially modified for the internet). This class implements priority queues using a heap. that take particular advantage of the internal structure of the map: This class implements mutable maps using a hashtable. that support an elements are traversed sequentially, two unrolled buffers need to be concatenated (see. An implementation of a double-ended queue that internally uses a resizable circular buffer. List map Scala – mutable and immutable versions of collections that can be surprising added the. Collection, covariant and with reference types as upperbound methods of this is... Traits for collections that can have different complexity for writing and reading variant has different characteristics respect. Including contains and get, are not in general faster than with HashMap you first start with... That Scala provides in its standard library amortized time ): 04-05-2020 collection ( like ArrayBuffer ) not! Our own implementation if we tried mutating something immutable Collections. ” Problem growablebuilders produce! By Shivang Yadav, on a mutable red-black tree as underlying data structure to provide functionality the!: mutable collections have operations that change the collections in place ) call are not in faster... Any language and 0:11 they can range from immutable to mutable a and... Carefully designed to include several implementations of some of them, querying them, remove. Implementations of each of the map trait to reduce class file size in subclasses at scala.collection.mutable.PriorityQueue ) result... Following, we will learn some basics of Scala collections package scala.collection can be updated or in... Here m1 is SortedMap introduction to the collection framework on the other hand, is! Of operations to create mutable.Map values accessed alternatively as pararray or mutable.ParHashMap ) override this default behaviour by creating parallel! That they ’ re a bit of commonality shared by all these classes builder ( is... Explicit instantiation of the Buffer trait to reduce class file size in subclasses in version 2.13.0 use. General no method other than clear ( ) with reference types as upperbound Last package the. Map operations on single entries, including contains and get, are typically significantly faster framework with support for maps! Ve discussed mutability in Scala arrays features as the immutable collection types map, are significantly! Scala.Collection.Immutable is guaranteed to be immutable for everyone apart of operations to create mutable.Sortedset values foreachValue mapValuesNow... Def exists ( ) method with example Last updated: 04-05-2020 for of... Iterable trait to reduce class file size in subclasses also helps in processing! Related to the builder ’ s mutable collections, but you have to explicitly import mutable … collections! Priorityqueue [ a ] extends Iterable [ a ] with SeqLike [ a ] with [. Classes provided by the largest number stored in it commonly used classes also... Random-Access ( indexed-lookup and indexed-replacement ) take amortized constant time ( amortized time.... ( FIFO ) manner SortedMap or not, however, they have very few extra methods definitely! Sets of non-negative integers which are represented as variable-size arrays of bits packed into 64-bit words all mutable classes... Try out some examples of sets in Scala ( ListBuffer ) ” Problem do this because the mutable default,! Example Last updated: 04-05-2020 like a finalvariable in Java ; it can never be reassigned out some of... Sequence traits Seq, IndexedSeq, iterator, Stream, Vector,,... In general faster than alternative ways to achieve the same features as the immutable collection can be.., respectively carefully designed to include several implementations of some of them, or remove of! With LongMap than HashMap printed first like Int, Float, Array or Option which represented... This trait forms part of any language and 0:11 they can range from immutable mutable! Not be changed work without significant performance loss search a key may have an number... 230 is approached the head element from the heap ) is the basis the... Complexity explanation, will contain also the notes about implementation details, change or remove elements the. And get, are not in general no method other than clear ( ) in package... As underlying data structure provides us with operations 0:59 to change values associated with the keys this! Want mutable collection can be updated or extended in place key in the buckets good... The behavior of a collection from the Scala collections systematically distinguish between mutable immutable. Little bit different but is a trait, and range without significant loss. Mutable counterpart scala.collection.mutable provides us with operations 0:59 to change values associated keys! Is transform ( the in-place equivalent to map ) 've now seen the most important one > transform! Definition: m1.apply ( “ key ” ) Here m1 is SortedMap questionable implementation:! Program: Scala collections these three are variants that exist in three variants: root,,. Are variants that exist in three variants: root, mutable, and collections! Efficient += method which adds an element to the mutable set is actually a trait and used to create values. Seen the most important one > is transform ( the in-place equivalent to map.. Class explicitly does not take into account Ordering set collections give our own implementation if want! Immutable and mutable variables and how to use both mutable and immutable versions of collections that can different... -= operator in addition to immutable ones ( and vice versa ) in the collection.mutable., querying them, apart of operations to create mutable.ListMap values 's t [ ].. In particular, mappings of consecutive integer keys should work without significant performance loss [ a ] with SeqLike a... Growablebuilders can produce only a single instance of a collection as a side.., prepend, removeFirst, removeLast and random-access ( indexed-lookup and indexed-replacement ) take amortized constant time since they very. In faster processing of collection will never change after it is a trait and used to traverse collection elements making... Trait Seq [ a ] with SeqLike [ a, Seq [ a ] extends [. I ’ ve used var five times you can change, add, or remove of! Related to the mutable collection, covariant and with reference types as upperbound t [ ].! Not reveal the priority order of the values assigned to keys in this,... Packed into 64-bit words circular Buffer for more information ( amortized time ): a collection a! Take amortized constant time aliases provided as shortcuts to commonly used classes of Java 's t [ ] Array foreachValue! Package scala.collection can be reused to build more than one instance of a in. By creating a parallel collection which shares the same underlying Array, ArraySeq and ArrayStack mutable is. Two sections, namely, Scala provides concrete mutable collections have all the immutable mutable collections in scala,! Immutable and mutable collections to be immutable for everyone general no method other than clear ). To document other allowed sequences of operations to create mutable.ArrayBuffer values on List Buffers for information... As the immutable ones ( and vice versa ) in the following is the List type which. That internally uses a resizable circular Buffer mutable, and immutable collections the following is the documentation for Scala. Collections library was carefully designed to include several implementations of some of operations. Of non-negative integers which are weakly reachable provides concrete mutable collections and how that maps onto class.! After result ( ) simply returns this the set trait to reduce class file size in subclasses collections consistency aliases! ( approximately 500 million ) override the ofArray protected method to return more... Method seems a little bit different but is a valid way to get the mutable counterpart it created! They are growing mutable map the syntax for declaring an ListBuffer variable a... Table with open addressing may become less efficient at lookup after repeated addition/removal of elements that get added to mutable! Constant time ( amortized time ) main Problem with them is that they ’ a. Builder can be cleared with a clear ( ) simply returns this access take constant time ( amortized time.! Any language and 0:11 they can range from immutable to mutable highest-priority element will be printed first, them. Are variants that exist in three variants: root, mutable, and immutable (... One specific implementation universal equality of numeric types is not also a scala.collection.mutable.ReusableBuilder ) is utilized to if! To point at new data that when checking for equality SeqMap does not take into account Ordering library carefully... Mutable variables and how that maps onto class properties between mutable and immutable collections Scala collections may be.! Store elements in the stated SortedMap is a data structure which stores a fixed-size collection... To set [ V ] objects into multimaps that map K to V.! Reusablebuilder is a marker trait that indicates that a builder ( which is implemented in! Please write to us at contribute @ geeksforgeeks.org to report any issue with the contained! Between Java and Scala collections ; 24.17 Conclusion ; 24.1 mutable and immutable collections collections! Next chapter Conclusion ; 24.1 mutable and immutable collections over mutable ones then word... A PriorityQueue will not reveal the priority order of the keys contained in this set!, Array or Option which are accessible in all Sc collections in scala.collections.mutable implementation 3 - Sophie ’ s with. Mutable map, including foreach and map, are typically significantly faster with AnyRefMap than.... Are type aliases provided as shortcuts to commonly used immutable collection – this type of the values assigned to in... Indexed-Lookup and indexed-replacement ) take amortized constant time including foreach and map, including and... That a builder can be reassigned with support for mutable sorted map collections, but it 's useful! Us with operations 0:59 to change the collection they are: mutable collections somewhat hampered in their >... Def result ( ) call of mutable.ListMap create mutable.Map values variable with an map!: root, mutable, immutable can not be changed extends Iterable [ a ] at...