System.Collections.Immutable 10.0.0-preview.5.25277.114

About

This package provides collections that are thread safe and guaranteed to never change their contents, also known as immutable collections. Like strings, any methods that perform modifications will not change the existing instance but instead return a new instance. For efficiency reasons, the implementation uses a sharing mechanism to ensure that newly created instances share as much data as possible with the previous instance while ensuring that operations have a predictable time complexity.

The System.Collections.Immutable library is built-in as part of the shared framework in .NET Runtime. The package can be installed when you need to use it in other target frameworks.

How to Use

using System.Collections.Immutable;

// Create immutable set of strings
ImmutableHashSet<string> colors = ImmutableHashSet.Create("Red", "Green", "Blue");

// Create a new set by adding and removing items from the original set
ImmutableHashSet<string> colorsModified = colors.Remove("Red").Add("Orange");

foreach (string s in colorsModified)
{
    Console.WriteLine(s);
}

/* Example output:
 Blue
 Green
 Orange
 */

Main Types

The main types provided by this library are:

  • System.Collections.Immutable.ImmutableArray
  • System.Collections.Immutable.ImmutableArray<T>
  • System.Collections.Immutable.ImmutableDictionary
  • System.Collections.Immutable.ImmutableDictionary<TKey,TValue>
  • System.Collections.Immutable.ImmutableHashSet
  • System.Collections.Immutable.ImmutableHashSet<T>
  • System.Collections.Immutable.ImmutableList
  • System.Collections.Immutable.ImmutableList<T>
  • System.Collections.Immutable.ImmutableQueue
  • System.Collections.Immutable.ImmutableQueue<T>
  • System.Collections.Immutable.ImmutableSortedDictionary
  • System.Collections.Immutable.ImmutableSortedDictionary<TKey,TValue>
  • System.Collections.Immutable.ImmutableSortedSet
  • System.Collections.Immutable.ImmutableSortedSet<T>
  • System.Collections.Immutable.ImmutableStack
  • System.Collections.Immutable.ImmutableStack<T>
  • System.Collections.Frozen.FrozenDictionary
  • System.Collections.Frozen.FrozenDictionary<TKey, TValue>
  • System.Collections.Frozen.FrozenSet
  • System.Collections.Frozen.FrozenSet<T>

Additional Documentation

Feedback & Contributing

System.Collections.Immutable is released as open source under the MIT license. Bug reports and contributions are welcome at the GitHub repository.

Showing the top 20 packages that depend on System.Collections.Immutable.

Packages Downloads
Microsoft.NETCore.App
A set of .NET API's that are included in the default .NET Core application model. 4c728dfede639432bd306b4de3f5b49585f3de18 When using NuGet 3.x this package requires at least version 3.4.
9
Microsoft.NETCore.App
A set of .NET API's that are included in the default .NET Core application model. When using NuGet 3.x this package requires at least version 3.4.
9
Microsoft.NETCore.App
A set of .NET API's that are included in the default .NET Core application model. d43032d4d97ce28daf2347ed735ebceca2a1f260 When using NuGet 3.x this package requires at least version 3.4.
9
Microsoft.NETCore.App
A set of .NET API's that are included in the default .NET Core application model. 37d16c2b4d50a6affc6886dd1d066b8e8aba2309 When using NuGet 3.x this package requires at least version 3.4.
9
System.Reflection.Metadata
This package provides a low-level .NET (ECMA-335) metadata reader and writer. It's geared for performance and is the ideal choice for building higher-level libraries that intend to provide their own object model, such as compilers. Commonly Used Types: System.Reflection.Metadata.MetadataReader System.Reflection.PortableExecutable.PEReader System.Reflection.Metadata.Ecma335.MetadataBuilder System.Reflection.PortableExecutable.PEBuilder System.Reflection.PortableExecutable.ManagedPEBuilder
9
System.Reflection.Metadata
This package provides a low-level .NET (ECMA-335) metadata reader and writer. It's geared for performance and is the ideal choice for building higher-level libraries that intend to provide their own object model, such as compilers. The metadata format is defined by the ECMA-335 - Common Language Infrastructure (CLI) specification. The System.Reflection.Metadata library is built-in as part of the shared framework in .NET Runtime. The package can be installed when you need to use it in other target frameworks.
9
Microsoft.CodeAnalysis.Common
A shared package used by the Microsoft .NET Compiler Platform ("Roslyn"). Do not install this package manually, it will be added as a prerequisite by other packages that require it. Supported Platforms: - .NET Framework 4.5 - Windows 8 - Portable Class Libraries
9
Microsoft.CodeAnalysis.Common
A shared package used by the Microsoft .NET Compiler Platform ("Roslyn"). Do not install this package manually, it will be added as a prerequisite by other packages that require it.
9
Microsoft.CodeAnalysis.Common
A shared package used by the Microsoft .NET Compiler Platform ("Roslyn"). Do not install this package manually, it will be added as a prerequisite by other packages that require it. More details at https://aka.ms/roslyn-packages This package was built from the source at https://github.com/dotnet/roslyn/commit/4c7d79a254288388d97d793c4087db6ebf00d2fd.
9
Microsoft.CodeAnalysis.Common
A shared package used by the Microsoft .NET Compiler Platform ("Roslyn"). Do not install this package manually, it will be added as a prerequisite by other packages that require it. More details at https://aka.ms/roslyn-packages This package was built from the source at https://github.com/dotnet/roslyn/commit/ae1fff344d46976624e68ae17164e0607ab68b10.
9
Microsoft.CodeAnalysis.Common
A shared package used by the Microsoft .NET Compiler Platform ("Roslyn"). Do not install this package manually, it will be added as a prerequisite by other packages that require it. More details at https://aka.ms/roslyn-packages This package was built from the source at https://github.com/dotnet/roslyn/commit/2f21c63bb29a816d4a62191a1a0739deb64d387c.
9
Microsoft.CodeAnalysis.Common
A shared package used by the Microsoft .NET Compiler Platform ("Roslyn"). Do not install this package manually, it will be added as a prerequisite by other packages that require it. More details at https://aka.ms/roslyn-packages This package was built from the source at https://github.com/dotnet/roslyn/commit/2242fa4fb945b97680bdd49eb5dd58285e4abb1c.
9
Microsoft.CodeAnalysis.Common
A shared package used by the Microsoft .NET Compiler Platform ("Roslyn"). Do not install this package manually, it will be added as a prerequisite by other packages that require it. More details at https://aka.ms/roslyn-packages This package was built from the source at https://github.com/dotnet/roslyn/commit/65df6b1065bae316232a6c9907a8be995302fb5e.
9
Microsoft.CodeAnalysis.Common
A shared package used by the Microsoft .NET Compiler Platform ("Roslyn"). Do not install this package manually, it will be added as a prerequisite by other packages that require it. More details at https://aka.ms/roslyn-packages This package was built from the source at https://github.com/dotnet/roslyn/commit/c3cc1d0ceeab1a65da0217e403851a1e8a30086a.
9
Grpc.Core
Core C# implementation of gRPC - an RPC library and framework. See project site for more info.
9
Microsoft.NETCore.App
A set of .NET API's that are included in the default .NET Core application model. 290303f510986f8f832fd2dc9e313cebe06ec68d When using NuGet 3.x this package requires at least version 3.4.
8
Microsoft.NETCore.App
A set of .NET API's that are included in the default .NET Core application model. When using NuGet 3.x this package requires at least version 3.4.
8

https://go.microsoft.com/fwlink/?LinkID=799421

.NET Framework 4.6.2

.NET 8.0

  • No dependencies.

.NET 9.0

  • No dependencies.

.NET 10.0

  • No dependencies.

.NET Standard 2.0

Version Downloads Last updated
10.0.0-rc.2.25502.107 2 10/20/2025
10.0.0-rc.1.25451.107 2 09/16/2025
10.0.0-preview.7.25380.108 3 09/05/2025
10.0.0-preview.6.25358.103 3 07/16/2025
10.0.0-preview.5.25277.114 4 06/26/2025
10.0.0-preview.4.25258.110 5 06/26/2025
10.0.0-preview.3.25171.5 6 06/26/2025
10.0.0-preview.2.25163.2 4 03/19/2025
10.0.0-preview.1.25080.5 4 03/19/2025
9.0.10 2 10/20/2025
9.0.9 3 09/16/2025
9.0.8 4 09/05/2025
9.0.7 3 07/16/2025
9.0.6 5 06/26/2025
9.0.5 5 07/07/2025
9.0.4 6 06/26/2025
9.0.3 7 03/19/2025
9.0.2 7 02/20/2025
9.0.1 6 02/04/2025
9.0.0 5 02/04/2025
9.0.0-rc.2.24473.5 6 02/04/2025
9.0.0-rc.1.24431.7 4 02/04/2025
9.0.0-preview.7.24405.7 5 02/04/2025
9.0.0-preview.6.24327.7 5 02/04/2025
9.0.0-preview.5.24306.7 3 02/04/2025
9.0.0-preview.4.24266.19 6 02/04/2025
9.0.0-preview.3.24172.9 3 02/04/2025
9.0.0-preview.2.24128.5 5 02/04/2025
9.0.0-preview.1.24080.9 5 02/04/2025
8.0.0 6 02/04/2025
8.0.0-rc.2.23479.6 5 02/04/2025
8.0.0-rc.1.23419.4 8 02/04/2025
8.0.0-preview.7.23375.6 5 02/05/2025
8.0.0-preview.6.23329.7 6 02/05/2025
8.0.0-preview.5.23280.8 5 02/04/2025
8.0.0-preview.4.23259.5 4 02/04/2025
8.0.0-preview.3.23174.8 6 02/04/2025
8.0.0-preview.2.23128.3 5 02/04/2025
8.0.0-preview.1.23110.8 5 02/05/2025
7.0.0 4 02/04/2025
7.0.0-rc.2.22472.3 5 02/04/2025
7.0.0-rc.1.22426.10 5 02/04/2025
7.0.0-preview.7.22375.6 5 02/04/2025
7.0.0-preview.6.22324.4 3 02/04/2025
7.0.0-preview.5.22301.12 5 02/04/2025
7.0.0-preview.4.22229.4 6 02/04/2025
7.0.0-preview.3.22175.4 4 02/05/2025
7.0.0-preview.2.22152.2 6 02/05/2025
7.0.0-preview.1.22076.8 4 02/05/2025
6.0.1 5 02/05/2025
6.0.0 6 02/05/2025
6.0.0-rc.2.21480.5 4 02/05/2025
6.0.0-rc.1.21451.13 6 02/05/2025
6.0.0-preview.7.21377.19 4 02/05/2025
6.0.0-preview.6.21352.12 5 02/05/2025
6.0.0-preview.5.21301.5 6 02/05/2025
6.0.0-preview.4.21253.7 4 02/05/2025
6.0.0-preview.3.21201.4 6 02/05/2025
6.0.0-preview.2.21154.6 7 02/05/2025
6.0.0-preview.1.21102.12 6 02/05/2025
5.0.0 4 02/04/2025
5.0.0-rc.2.20475.5 5 02/04/2025
5.0.0-rc.1.20451.14 6 02/04/2025
5.0.0-preview.8.20407.11 4 02/04/2025
5.0.0-preview.7.20364.11 6 02/04/2025
5.0.0-preview.6.20305.6 4 02/04/2025
5.0.0-preview.5.20278.1 5 02/04/2025
5.0.0-preview.4.20251.6 5 02/04/2025
5.0.0-preview.3.20214.6 6 02/04/2025
5.0.0-preview.2.20160.6 5 02/04/2025
5.0.0-preview.1.20120.5 5 02/05/2025
1.7.1 6 02/05/2025
1.7.0 6 02/05/2025
1.7.0-preview3.19551.4 7 02/05/2025
1.7.0-preview2.19523.17 4 02/05/2025
1.7.0-preview1.19504.10 3 02/05/2025
1.6.0 7 02/05/2025
1.6.0-rc1.19456.4 5 02/05/2025
1.6.0-preview9.19421.4 4 02/05/2025
1.6.0-preview9.19416.11 6 02/05/2025
1.6.0-preview8.19405.3 5 02/05/2025
1.6.0-preview7.19362.9 6 02/05/2025
1.6.0-preview6.19303.8 5 02/05/2025
1.6.0-preview6.19264.9 5 02/05/2025
1.6.0-preview5.19224.8 5 02/05/2025
1.6.0-preview4.19212.13 4 02/05/2025
1.6.0-preview3.19128.7 4 02/05/2025
1.6.0-preview.19073.11 4 02/05/2025
1.6.0-preview.18571.3 5 02/05/2025
1.5.0 5 02/05/2025
1.5.0-rc1 5 02/05/2025
1.5.0-preview2-26406-04 4 02/05/2025
1.5.0-preview1-26216-02 5 02/05/2025
1.4.0 6 02/05/2025
1.4.0-preview2-25405-01 6 02/05/2025
1.4.0-preview1-25305-02 6 02/05/2025
1.3.1 5 02/05/2025
1.3.0 6 02/05/2025
1.3.0-preview1-24530-04 4 02/05/2025
1.2.0 6 02/05/2025
1.2.0-rc2-24027 6 02/05/2025
1.1.38-beta-23516 5 02/05/2025
1.1.38-beta-23409 5 02/05/2025
1.1.38-beta-23225 6 02/05/2025
1.1.37 6 02/05/2025
1.1.37-beta-23109 5 02/05/2025
1.1.37-beta-23019 6 02/05/2025
1.1.36 6 02/05/2025
1.1.34-rc 4 02/05/2025
1.1.33-beta 5 02/05/2025
1.1.32-beta 5 02/05/2025