System.Collections.Immutable Namespace

Contains interfaces and classes that define immutable collections.

Classes

Name	Description
ImmutableArray	Provides methods for creating an array that is immutable, meaning it can't be changed once it's created.
ImmutableArray<T>.Builder	Represents a writable array accessor that can be converted into an ImmutableArray<T> instance without allocating extra memory.
ImmutableDictionary	Provides a set of initialization methods for instances of the ImmutableDictionary<TKey,TValue> class.
ImmutableDictionary<TKey,TValue>.Builder	Represents a hash map that mutates with little or no memory allocations and that can produce or build on immutable hash map instances efficiently.
ImmutableDictionary<TKey,TValue>	Represents an immutable, unordered collection of keys and values.
ImmutableHashSet	Provides a set of initialization methods for instances of the ImmutableHashSet<T> class.
ImmutableHashSet<T>.Builder	Represents a hash set that mutates with little or no memory allocations and that can produce or build on immutable hash set instances efficiently.
ImmutableHashSet<T>	Represents an immutable, unordered hash set.
ImmutableInterlocked	Contains interlocked exchange mechanisms for immutable collections.
ImmutableList	Provides a set of initialization methods for instances of the ImmutableList<T> class.
ImmutableList<T>.Builder	Represents a list that mutates with little or no memory allocations and that can produce or build on immutable list instances efficiently.
ImmutableList<T>	Represents an immutable list, which is a strongly typed list of objects that can be accessed by index.
ImmutableQueue	Provides a set of initialization methods for instances of the ImmutableQueue<T> class.
ImmutableQueue<T>	Represents an immutable queue.
ImmutableSortedDictionary	Provides a set of initialization methods for instances of the ImmutableSortedDictionary<TKey,TValue> class.
ImmutableSortedDictionary<TKey,TValue>.Builder	Represents a sorted dictionary that mutates with little or no memory allocations and that can produce or build on immutable sorted dictionary instances efficiently.
ImmutableSortedDictionary<TKey,TValue>	Represents an immutable sorted dictionary.
ImmutableSortedSet	Provides a set of initialization methods for instances of the ImmutableSortedSet<T> class.
ImmutableSortedSet<T>.Builder	Represents a sorted set that enables changes with little or no memory allocations, and efficiently manipulates or builds immutable sorted sets.
ImmutableSortedSet<T>	Represents an immutable sorted set implementation.
ImmutableStack	Provides a set of initialization methods for instances of the ImmutableStack<T> class.
ImmutableStack<T>	Represents an immutable stack.

Structs

Name	Description
ImmutableArray<T>.Enumerator	Represents an array enumerator.
ImmutableArray<T>	Represents an array that is immutable, meaning it can't be changed once it's created.
ImmutableDictionary<TKey,TValue>.Enumerator	Enumerates the contents of the immutable dictionary without allocating any memory.
ImmutableHashSet<T>.Enumerator	Enumerates the contents of the immutable hash set without allocating any memory.
ImmutableList<T>.Enumerator	Enumerates the contents of a binary tree.
ImmutableQueue<T>.Enumerator	Enumerates the contents of an immutable queue without allocating any memory.
ImmutableSortedDictionary<TKey,TValue>.Enumerator	Enumerates the contents of a binary tree.
ImmutableSortedSet<T>.Enumerator	Enumerates the contents of a binary tree.
ImmutableStack<T>.Enumerator	Enumerates the contents of an immutable stack without allocating any memory.

Interfaces

Name	Description
IImmutableDictionary<TKey,TValue>	Represents an immutable collection of key/value pairs.
IImmutableList<T>	Represents a list of elements that cannot be modified.
IImmutableQueue<T>	Represents an immutable first-in, first-out collection of objects.
IImmutableSet<T>	Represents a set of elements that can only be modified by creating a new instance of the set.
IImmutableStack<T>	Represents an immutable last-in-first-out (LIFO) collection.

Remarks

With immutable collections, you can:

• Share a collection in a way that its consumer can be assured that the collection never changes.
• Provide implicit thread safety in multi-threaded applications (no locks required to access collections).
• Follow functional programming practices.
• Modify a collection during enumeration, while ensuring that the original collection does not change.