https://github.com/simoncropp/polyfill

Source only package that exposes newer APIs, .net features, and C# features to older runtimes.
https://github.com/simoncropp/polyfill
Last synced: 2 months ago
JSON representation
Source only package that exposes newer APIs, .net features, and C# features to older runtimes.
Host: GitHub
URL: https://github.com/simoncropp/polyfill
Owner: SimonCropp
License: mit
Created: 2023-03-02T22:42:46.000Z (over 2 years ago)
Default Branch: main
Last Pushed: 2025-05-14T10:32:09.000Z (2 months ago)
Last Synced: 2025-05-14T11:46:52.384Z (2 months ago)
Language: C#
Homepage:
Size: 1.56 MB
Stars: 356
Watchers: 5
Forks: 29
Open Issues: 0
Metadata Files:
- Readme: readme.md
- Contributing: contributing.md
- Funding: .github/FUNDING.yml
- License: license.txt
- Code of conduct: code_of_conduct.md
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README

        #  Polyfill

[![Build status](https://ci.appveyor.com/api/projects/status/s6eqqg4ipeovebgd?svg=true)](https://ci.appveyor.com/project/SimonCropp/Polyfill)

[![Polyfill NuGet Status](https://img.shields.io/nuget/v/Polyfill.svg)](https://www.nuget.org/packages/Polyfill/)

Source only package that exposes newer .NET and C# features to older runtimes.

The package targets `netstandard2.0` and is designed to support the following runtimes.

 * `net461`, `net462`, `net47`, `net471`, `net472`, `net48`, `net481`

 * `netcoreapp2.0`, `netcoreapp2.1`, `netcoreapp3.0`, `netcoreapp3.1`

 * `net5.0`, `net6.0`, `net7.0`, `net8.0`, `net9.0`, `net10.0`

**API count: 590**

**See [Milestones](../../milestones?state=closed) for release notes.**

### Powered by

[![JetBrains logo.](https://resources.jetbrains.com/storage/products/company/brand/logos/jetbrains.svg)](https://jb.gg/OpenSourceSupport)

## TargetFrameworks

Some polyfills are implemented in a way that will not always have the equivalent performance to the actual implementations.

For example the polyfill for `StringBuilder.Append(ReadOnlySpan)` on netcore2 is:

```

public StringBuilder Append(ReadOnlySpan value)

    => target.Append(value.ToString());

```

Which will result in a string allocation.

As Polyfill is implemented as a source only nuget, the implementation for each polyfill is compiled into the IL of the consuming assembly. As a side-effect that implementation will continue to be used even if that assembly is executed in a runtime that has a more efficient implementation available.

As a result, in the context of a project producing nuget package, that project should target all frameworks from the lowest TargetFramework up to and including the current framework. This way the most performant implementation will be used for each runtime. Take the following examples:

 * If a nuget's minimum target is net6, then the resulting TargetFrameworks should also include net7.0 and net8.0

 * If a nuget's minimum target is net471, then the resulting TargetFrameworks should also include net472 and net48"

## Nuget

https://nuget.org/packages/Polyfill/

## SDK / LangVersion

This project uses features from the current stable SDK and C# language. As such consuming projects should target those:

### LangVersion

```xml

  

    latest

```

### global.json

```json

{

  "sdk": {

    "version": "9.0.202",

    "rollForward": "latestFeature"

  }

}

```

## Consuming and type visibility

The default type visibility for all polyfills is `internal`. This means it can be consumed in multiple projects and types will not conflict.

### Consuming in an app

If Polyfill is being consumed in a solution that produce an app, then it is recommended to use the Polyfill nuget only in the root "app project" and enable `PolyPublic`.

```xml

  

    true

```

Then all consuming projects, like tests, will not need to use the Polyfill nuget.

### Consuming in a library

If Polyfill is being consumed in a solution that produce a library (and usually a nuget), then the Polyfill nuget can be added to all projects.

If, however, `InternalsVisibleTo` is being used to expose APIs (for example to test projects), then the Polyfill nuget should be added only to the root library project.

## Troubleshooting

Make sure `DefineConstants` is not set from dotnet CLI, which would override important constants set by Polyfill.

Instead of using `dotnet publish -p:DefineConstants=MY_CONSTANT`, set the constant indirectly in the project:

```xml

  

    $(DefineConstants);MY_CONSTANT

```

and use `dotnet publish -p:MyConstant=true`.

## Included polyfills

### ModuleInitializerAttribute

 * [ModuleInitializerAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.compilerservices.moduleinitializerattribute)

Reference: [Module Initializers](https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/proposals/csharp-9.0/module-initializers)



```cs

static bool InitCalled;

[Test]

public void ModuleInitTest() =>

    Assert.True(InitCalled);

[ModuleInitializer]

public static void ModuleInit() =>

    InitCalled = true;

```

^{snippet source | anchor}

### IsExternalInit

Reference: [init (C# Reference)](https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/init)



```cs

class InitSample

{

    public int Member { get; init; }

}

```

^{snippet source | anchor}

### Nullable attributes

  * [AllowNullAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.allownullattribute)

  * [DisallowNullAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.disallownullattribute)

  * [DoesNotReturnAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.doesnotreturnattribute)

  * [DoesNotReturnIfAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.doesnotreturnifattribute)

  * [MaybeNullAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.maybenullattribute)

  * [MaybeNullWhenAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.maybenullwhenattribute)

  * [MemberNotNullAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.membernotnullattribute)

  * [MemberNotNullWhenAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.membernotnullwhenattribute)

  * [NotNullAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.notnullattribute)

  * [NotNullIfNotNullAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.notnullifnotnullattribute)

  * [NotNullWhenAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.notnullwhenattribute)

Reference: [Nullable reference types](https://learn.microsoft.com/en-us/dotnet/csharp/nullable-references)

### Required attributes

 * [RequiredMemberAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.compilerservices.requiredmemberattribute)

 * [SetsRequiredMembersAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.setsrequiredmembersattribute)

Reference: [C# required modifier](https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/required)



```cs

public class Person

{

    public Person()

    {

    }

    [SetsRequiredMembers]

    public Person(string name) =>

        Name = name;

    public required string Name { get; init; }

}

```

^{snippet source | anchor}

### CompilerFeatureRequiredAttribute

 * [CompilerFeatureRequiredAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.compilerservices.compilerfeaturerequiredattribute)

> Indicates that compiler support for a particular feature is required for the location where this attribute is applied.

### CollectionBuilderAttribute

 * [CollectionBuilderAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.compilerservices.collectionbuilderattribute)

> Can be used to make types compatible with collection expressions

### ConstantExpectedAttribute

 * [ConstantExpectedAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.constantexpectedattribute)

> Indicates that the specified method parameter expects a constant.

### SkipLocalsInit

 * [SkipLocalsInitAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.compilerservices.skiplocalsinitattribute)

Reference: [SkipLocalsInitAttribute](https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/attributes/general#skiplocalsinit-attribute)

> the SkipLocalsInit attribute prevents the compiler from setting the .locals init flag when emitting to metadata. The SkipLocalsInit attribute is a single-use attribute and can be applied to a method, a property, a class, a struct, an interface, or a module, but not to an assembly. SkipLocalsInit is an alias for SkipLocalsInitAttribute.



```cs

class SkipLocalsInitSample

{

    [SkipLocalsInit]

    static void ReadUninitializedMemory()

    {

        Span numbers = stackalloc int[120];

        for (var i = 0; i < 120; i++)

        {

            Console.WriteLine(numbers[i]);

        }

    }

}

```

^{snippet source | anchor}

### Index and Range

Reference: [Indices and ranges](https://learn.microsoft.com/en-us/dotnet/csharp/tutorials/ranges-indexes)

If consuming in a project that targets net461 or net462, a reference to System.ValueTuple is required. See [References: System.ValueTuple](#systemvaluetuple).



```cs

[TestFixture]

class IndexRangeSample

{

    [Test]

    public void Range()

    {

        var substring = "value"[2..];

        Assert.AreEqual("lue", substring);

    }

    [Test]

    public void Index()

    {

        var ch = "value"[^2];

        Assert.AreEqual('u', ch);

    }

    [Test]

    public void ArrayIndex()

    {

        var array = new[]

        {

            "value1",

            "value2"

        };

        var value = array[^2];

        Assert.AreEqual("value1", value);

    }

}

```

^{snippet source | anchor}

### OverloadResolutionPriority

 * [Release Notes](https://github.com/dotnet/core/blob/main/release-notes/9.0/preview/preview7/csharp.md#prioritize-better-overloads-with-overloadresolutionpriority-attribute)

> C# introduces a new attribute, System.Runtime.CompilerServices.OverloadResolutionPriority, that can be used by API authors to adjust the relative priority of overloads within a single type as a means of steering API consumers to use specific APIs, even if those APIs would normally be considered ambiguous or otherwise not be chosen by C#'s overload resolution rules. This helps framework and library authors guide API usage as they APIs as they develop new and better patterns.

>

> The OverloadResolutionPriorityAttribute can be used in conjunction with the ObsoleteAttribute. A library author may mark properties, methods, types and other programming elements as obsolete, while leaving them in place for backwards compatibility. Using programming elements marked with the ObsoleteAttribute will result in compiler warnings or errors. However, the type or member is still visible to overload resolution and may be selected over a better overload or cause an ambiguity failure. The OverloadResolutionPriorityAttribute lets library authors fix these problems by lowering the priority of obsolete members when there are better alternatives.

 * [API on learn](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.compilerservices.overloadresolutionpriorityattribute.-ctor)

 * [API Proposal](https://github.com/dotnet/runtime/issues/102173)

#### Usage



```cs

[TestFixture]

public class OverloadResolutionPriorityAttributeTests

{

    [Test]

    public void Run()

    {

        int[] arr = [1, 2, 3];

        //Prints "Span" because resolution priority is higher

        Method(arr);

    }

    [OverloadResolutionPriority(2)]

    static void Method(ReadOnlySpan list) =>

        Console.WriteLine("Span");

    [OverloadResolutionPriority(1)]

    static void Method(int[] list) =>

        Console.WriteLine("Array");

}

```

^{snippet source | anchor}

### UnscopedRefAttribute

 * [UnscopedRefAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.unscopedrefattribute)

Reference: [Low Level Struct Improvements](https://github.com/dotnet/csharplang/blob/main/proposals/csharp-11.0/low-level-struct-improvements.md)



```cs

struct UnscopedRefUsage

{

    int field1;

    [UnscopedRef] ref int Prop1 => ref field1;

}

```

^{snippet source | anchor}

### RequiresPreviewFeaturesAttribute

 * [RequiresPreviewFeatures](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.versioning.requirespreviewfeaturesattribute)

 * [Design](https://github.com/dotnet/designs/blob/main/accepted/2021/preview-features/preview-features.md)

 * [API Proposal](https://github.com/dapr/dotnet-sdk/issues/1219)

### CallerArgumentExpressionAttribute

 * [CallerArgumentExpressionAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.compilerservices.callerargumentexpressionattribute)

Reference: [CallerArgumentExpression](https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/proposals/csharp-10.0/caller-argument-expression)



```cs

static class FileUtil

{

    public static void FileExists(string path, [CallerArgumentExpression("path")] string argumentName = "")

    {

        if (!File.Exists(path))

        {

            throw new ArgumentException($"File not found. Path: {path}", argumentName);

        }

    }

}

static class FileUtilUsage

{

    public static string[] Method(string path)

    {

        FileUtil.FileExists(path);

        return File.ReadAllLines(path);

    }

}

```

^{snippet source | anchor}

### InterpolatedStringHandler

 * [AppendInterpolatedStringHandler](https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder.appendinterpolatedstringhandler)

 * [DefaultInterpolatedStringHandler](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.compilerservices.defaultinterpolatedstringhandler)

 * [InterpolatedStringHandlerAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.compilerservices.interpolatedstringhandlerattribute)

 * [InterpolatedStringHandlerArgumentAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.compilerservices.interpolatedstringhandlerargumentattribute)

 * [ISpanFormattable](https://learn.microsoft.com/en-us/dotnet/api/system.ispanformattable)

References: [String Interpolation in C# 10 and .NET 6](https://devblogs.microsoft.com/dotnet/string-interpolation-in-c-10-and-net-6/), [Write a custom string interpolation handler](https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/tutorials/interpolated-string-handler)

### StringSyntaxAttribute

 * [StringSyntaxAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.stringsyntaxattribute)

Reference: [.NET 7 - The StringSyntaxAttribute](https://bartwullems.blogspot.com/2022/12/net-7-stringsyntaxattribute.html)

### Trimming annotation attributes

 * [DynamicallyAccessedMembersAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.dynamicallyaccessedmembersattribute)

 * [DynamicDependencyAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.dynamicdependencyattribute)

 * [RequiresUnreferencedCodeAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.requiresunreferencedcodeattribute)

 * [RequiresDynamicCodeAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.requiresdynamiccodeattribute)

 * [UnconditionalSuppressMessageAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.codeanalysis.unconditionalsuppressmessageattribute)

Reference: [Prepare .NET libraries for trimming](https://learn.microsoft.com/en-us/dotnet/core/deploying/trimming/prepare-libraries-for-trimming)

### Platform compatibility

 * [ObsoletedOSPlatformAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.versioning.obsoletedosplatformattribute)

 * [SupportedOSPlatformAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.versioning.supportedosplatformattribute)

 * [SupportedOSPlatformGuardAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.versioning.supportedosplatformguardattribute)

 * [TargetPlatformAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.versioning.targetplatformattribute)

 * [UnsupportedOSPlatformAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.versioning.unsupportedosplatformattribute)

 * [UnsupportedOSPlatformGuardAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.versioning.unsupportedosplatformguardattribute)

Reference: [Platform compatibility analyzer](https://learn.microsoft.com/en-us/dotnet/standard/analyzers/platform-compat-analyzer)

### StackTraceHiddenAttribute

 * [StackTraceHiddenAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.stacktracehiddenattribute)

Reference: [C# – Hide a method from the stack trace](https://makolyte.com/csharp-exclude-exception-throw-helper-methods-from-the-stack-trace/)

### UnmanagedCallersOnly

 * [UnmanagedCallersOnlyAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.interopservices.unmanagedcallersonlyattribute)

Reference: [Improvements in native code interop in .NET 5.0](https://devblogs.microsoft.com/dotnet/improvements-in-native-code-interop-in-net-5-0/)

### SuppressGCTransition

 * [SuppressGCTransitionAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.interopservices.suppressgctransitionattribute)

### DisableRuntimeMarshalling

 * [DisableRuntimeMarshallingAttribute](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.compilerservices.disableruntimemarshallingattribute)

## Extensions

The class `Polyfill` includes the following extension methods:

> [!IMPORTANT]

> The methods using `AppendInterpolatedStringHandler` parameter are not extensions because the compiler prefers to use the overload with `string` parameter instead.

### Extension methods

#### bool

 * `bool TryFormat(bool, Span, int)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.boolean.tryformat)

#### byte

 * `bool TryFormat(byte, Span, int, ReadOnlySpan, IFormatProvider?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.byte.tryformat#system-byte-tryformat(system-span((system-byte))-system-int32@-system-readonlyspan((system-char))-system-iformatprovider))

 * `bool TryFormat(byte, Span, int, ReadOnlySpan, IFormatProvider?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.byte.tryformat#system-byte-tryformat(system-span((system-char))-system-int32@-system-readonlyspan((system-char))-system-iformatprovider))

#### CancellationToken

 * `CancellationTokenRegistration Register(CancellationToken, Action, object?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.threading.cancellationtoken.register#system-threading-cancellationtoken-register(system-action((system-object-system-threading-cancellationtoken))-system-object))

 * `CancellationTokenRegistration UnsafeRegister(CancellationToken, Action, object?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.threading.cancellationtoken.unsaferegister#system-threading-cancellationtoken-unsaferegister(system-action((system-object))-system-object))

 * `CancellationTokenRegistration UnsafeRegister(CancellationToken, Action, object?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.threading.cancellationtoken.unsaferegister#system-threading-cancellationtoken-unsaferegister(system-action((system-object-system-threading-cancellationtoken))-system-object))

#### CancellationTokenSource

 * `Task CancelAsync(CancellationTokenSource)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.threading.cancellationtokensource.cancelasync)

#### ConcurrentBag

 * `void Clear(ConcurrentBag)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.concurrent.concurrentbag-1.clear)

#### ConcurrentDictionary

 * `TValue GetOrAdd(ConcurrentDictionary, TKey, Func, TArg) where TKey : notnull` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.concurrent.concurrentdictionary-2.getoradd#system-collections-concurrent-concurrentdictionary-2-getoradd-1(-0-system-func((-0-0-1))-0))

#### ConcurrentQueue

 * `void Clear(ConcurrentQueue)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.concurrent.concurrentqueue-1.clear)

#### DateOnly

 * `void Deconstruct(DateOnly, int, int, int)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.dateonly.deconstruct)

 * `bool TryFormat(DateOnly, Span, int, ReadOnlySpan, IFormatProvider?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.dateonly.tryformat#system-dateonly-tryformat(system-span((system-byte))-system-int32@-system-readonlyspan((system-char))-system-iformatprovider))

 * `bool TryFormat(DateOnly, Span, int, ReadOnlySpan, IFormatProvider?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.dateonly.tryformat#system-dateonly-tryformat(system-span((system-char))-system-int32@-system-readonlyspan((system-char))-system-iformatprovider))

#### DateTime

 * `DateTime AddMicroseconds(DateTime, double)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.datetime.addmicroseconds)

 * `void Deconstruct(DateTime, int, int, int)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.datetime.deconstruct#system-datetime-deconstruct(system-int32@-system-int32@-system-int32@))

 * `void Deconstruct(DateTime, DateOnly, TimeOnly)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.datetime.deconstruct#system-datetime-deconstruct(system-dateonly@-system-timeonly@))

 * `int Microsecond(DateTime)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.datetime.microsecond)

 * `int Nanosecond(DateTime)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.datetime.nanosecond)

 * `bool TryFormat(DateTime, Span, int, ReadOnlySpan, IFormatProvider?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.datetime.tryformat#system-datetime-tryformat(system-span((system-byte))-system-int32@-system-readonlyspan((system-char))-system-iformatprovider))

 * `bool TryFormat(DateTime, Span, int, ReadOnlySpan, IFormatProvider?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.datetime.tryformat#system-datetime-tryformat(system-span((system-char))-system-int32@-system-readonlyspan((system-char))-system-iformatprovider))

#### DateTimeOffset

 * `DateTimeOffset AddMicroseconds(DateTimeOffset, double)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.datetimeoffset.addmicroseconds)

 * `void Deconstruct(DateTimeOffset, DateOnly, TimeOnly, TimeSpan)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.datetimeoffset.deconstruct)

 * `int Microsecond(DateTimeOffset)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.datetimeoffset.microsecond)

 * `int Nanosecond(DateTimeOffset)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.datetimeoffset.nanosecond)

 * `bool TryFormat(DateTimeOffset, Span, int, ReadOnlySpan, IFormatProvider?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.datetimeoffset.tryformat#system-datetimeoffset-tryformat(system-span((system-byte))-system-int32@-system-readonlyspan((system-char))-system-iformatprovider))

 * `bool TryFormat(DateTimeOffset, Span, int, ReadOnlySpan, IFormatProvider?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.datetimeoffset.tryformat#system-datetimeoffset-tryformat(system-span((system-char))-system-int32@-system-readonlyspan((system-char))-system-iformatprovider))

#### decimal

 * `bool TryFormat(decimal, Span, int, ReadOnlySpan, IFormatProvider?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.decimal.tryformat#system-decimal-tryformat(system-span((system-byte))-system-int32@-system-readonlyspan((system-char))-system-iformatprovider))

 * `bool TryFormat(decimal, Span, int, ReadOnlySpan, IFormatProvider?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.decimal.tryformat#system-decimal-tryformat(system-span((system-char))-system-int32@-system-readonlyspan((system-char))-system-iformatprovider))

#### DefaultInterpolatedStringHandler

 * `void Clear(DefaultInterpolatedStringHandler)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.compilerservices.defaultinterpolatedstringhandler.clear)

#### Delegate

 * `bool HasSingleTarget(Delegate)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.delegate.hassingletarget)

#### Dictionary

 * `void EnsureCapacity(Dictionary, int)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.dictionary-2.ensurecapacity)

 * `void TrimExcess(Dictionary, int)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.dictionary-2.trimexcess#system-collections-generic-dictionary-2-trimexcess(system-int32))

 * `void TrimExcess(Dictionary)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.dictionary-2.ensurecapacity)

#### DictionaryEntry

 * `void Deconstruct(DictionaryEntry, object, object?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.dictionaryentry.deconstruct#system-collections-dictionaryentry-deconstruct(system-object@-system-object@))

#### double

 * `bool TryFormat(double, Span, int, ReadOnlySpan, IFormatProvider?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.double.tryformat#system-double-tryformat(system-span((system-byte))-system-int32@-system-readonlyspan((system-char))-system-iformatprovider))

 * `bool TryFormat(double, Span, int, ReadOnlySpan, IFormatProvider?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.double.tryformat#system-double-tryformat(system-span((system-char))-system-int32@-system-readonlyspan((system-char))-system-iformatprovider))

#### Encoding

 * `int GetByteCount(Encoding, ReadOnlySpan)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.encoding.getbytecount#system-text-encoding-getbytecount(system-readonlyspan((system-char))))

 * `int GetBytes(Encoding, ReadOnlySpan, Span)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.encoding.getbytes#system-text-encoding-getbytes(system-readonlyspan((system-char))-system-span((system-byte))))

 * `int GetCharCount(Encoding, ReadOnlySpan)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.encoding.getcharcount#system-text-encoding-getcharcount(system-readonlyspan((system-byte))))

 * `int GetChars(Encoding, ReadOnlySpan, Span)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.encoding.getchars#system-text-encoding-getchars(system-readonlyspan((system-byte))-system-span((system-char))))

 * `string GetString(Encoding, ReadOnlySpan)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.encoding.getstring#system-text-encoding-getstring(system-readonlyspan((system-byte))))

 * `bool TryGetBytes(Encoding, ReadOnlySpan, Span, int)`

 * `bool TryGetChars(Encoding, ReadOnlySpan, Span, int)`

#### EventInfo

 * `NullabilityState GetNullability(EventInfo)`

 * `NullabilityInfo GetNullabilityInfo(EventInfo)`

 * `bool IsNullable(EventInfo)`

#### FieldInfo

 * `NullabilityState GetNullability(FieldInfo)`

 * `NullabilityInfo GetNullabilityInfo(FieldInfo)`

 * `bool IsNullable(FieldInfo)`

#### float

 * `bool TryFormat(float, Span, int, ReadOnlySpan, IFormatProvider?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.single.tryformat#system-single-tryformat(system-span((system-byte))-system-int32@-system-readonlyspan((system-char))-system-iformatprovider))

 * `bool TryFormat(float, Span, int, ReadOnlySpan, IFormatProvider?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.single.tryformat#system-single-tryformat(system-span((system-char))-system-int32@-system-readonlyspan((system-char))-system-iformatprovider))

#### Guid

 * `bool TryFormat(Guid, Span, int, ReadOnlySpan)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.guid.tryformat#system-guid-tryformat(system-span((system-byte))-system-int32@-system-readonlyspan((system-char))))

 * `bool TryFormat(Guid, Span, int, ReadOnlySpan)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.guid.tryformat#system-guid-tryformat(system-span((system-char))-system-int32@-system-readonlyspan((system-char))))

#### HashSet

 * `void EnsureCapacity(HashSet, int)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.hashset-1.ensurecapacity#system-collections-generic-hashset-1-ensurecapacity(system-int32))

 * `void TrimExcess(HashSet, int)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.hashset-1.trimexcess?#system-collections-generic-hashset-1-trimexcess(system-int32))

 * `bool TryGetValue(HashSet, T, T)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.hashset-1.trygetvalue)

#### HttpClient

 * `Task GetByteArrayAsync(HttpClient, string, CancellationToken)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.net.http.httpclient.getbytearrayasync#system-net-http-httpclient-getbytearrayasync(system-string-system-threading-cancellationtoken))

 * `Task GetByteArrayAsync(HttpClient, Uri, CancellationToken)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.net.http.httpclient.getbytearrayasync#system-net-http-httpclient-getbytearrayasync(system-uri-system-threading-cancellationtoken))

 * `Task GetStreamAsync(HttpClient, string, CancellationToken)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.net.http.httpclient.getstreamasync#system-net-http-httpclient-getstreamasync(system-string-system-threading-cancellationtoken))

 * `Task GetStreamAsync(HttpClient, Uri, CancellationToken)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.net.http.httpclient.getstreamasync#system-net-http-httpclient-getstreamasync(system-uri-system-threading-cancellationtoken))

 * `Task GetStringAsync(HttpClient, string, CancellationToken)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.net.http.httpclient.getstringasync#system-net-http-httpclient-getstringasync(system-string-system-threading-cancellationtoken))

 * `Task GetStringAsync(HttpClient, Uri, CancellationToken)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.net.http.httpclient.getstringasync#system-net-http-httpclient-getstringasync(system-uri-system-threading-cancellationtoken))

#### HttpContent

 * `Task ReadAsByteArrayAsync(HttpContent, CancellationToken)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.net.http.httpcontent.readasbytearrayasync#system-net-http-httpcontent-readasbytearrayasync(system-threading-cancellationtoken))

 * `Task ReadAsStreamAsync(HttpContent, CancellationToken)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.net.http.httpcontent.readasstreamasync#system-net-http-httpcontent-readasstreamasync(system-threading-cancellationtoken))

 * `Task ReadAsStringAsync(HttpContent, CancellationToken)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.net.http.httpcontent.readasstringasync#system-net-http-httpcontent-readasstringasync(system-threading-cancellationtoken))

#### IDictionary

 * `ReadOnlyDictionary AsReadOnly(IDictionary) where TKey : notnull` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.collectionextensions.asreadonly#system-collections-generic-collectionextensions-asreadonly-2(system-collections-generic-idictionary((-0-1))))

 * `bool Remove(IDictionary, TKey, TValue) where TKey : notnull` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.collectionextensions.remove)

 * `bool TryAdd(IDictionary, TKey, TValue) where TKey : notnull` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.collectionextensions.tryadd)

#### IEnumerable

 * `IEnumerable<(TFirst First, TSecond Second, TThird Third)> Zip(IEnumerable, IEnumerable, IEnumerable)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.zip#system-linq-enumerable-zip-3(system-collections-generic-ienumerable((-0))-system-collections-generic-ienumerable((-1))-system-collections-generic-ienumerable((-2))))

 * `IEnumerable<(TFirst First, TSecond Second)> Zip(IEnumerable, IEnumerable)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.zip#system-linq-enumerable-zip-2(system-collections-generic-ienumerable((-0))-system-collections-generic-ienumerable((-1))))

#### IEnumerable

 * `IEnumerable> AggregateBy(IEnumerable, Func, TAccumulate, Func, IEqualityComparer?) where TKey : notnull` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.aggregateby#system-linq-enumerable-aggregateby-3(system-collections-generic-ienumerable((-0))-system-func((-0-1))-system-func((-1-2))-system-func((-2-0-2))-system-collections-generic-iequalitycomparer((-1))))

 * `IEnumerable> AggregateBy(IEnumerable, Func, Func, Func, IEqualityComparer?) where TKey : notnull` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.aggregateby#system-linq-enumerable-aggregateby-3(system-collections-generic-ienumerable((-0))-system-func((-0-1))-2-system-func((-2-0-2))-system-collections-generic-iequalitycomparer((-1))))

 * `IEnumerable Append(IEnumerable, TSource)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.append)

 * `IEnumerable Chunk(IEnumerable, int)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.chunk)

 * `IEnumerable> CountBy(IEnumerable, Func, IEqualityComparer?) where TKey : notnull` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.countby)

 * `IEnumerable DistinctBy(IEnumerable, Func)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.distinctby#system-linq-enumerable-distinctby-2(system-collections-generic-ienumerable((-0))-system-func((-0-1))))

 * `IEnumerable DistinctBy(IEnumerable, Func, IEqualityComparer)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.distinctby#system-linq-enumerable-distinctby-2(system-collections-generic-ienumerable((-0))-system-func((-0-1))-system-collections-generic-iequalitycomparer((-1))))

 * `TSource ElementAt(IEnumerable, Index)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.elementat#system-linq-enumerable-elementat-1(system-collections-generic-ienumerable((-0))-system-index))

 * `TSource? ElementAtOrDefault(IEnumerable, Index)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.elementatordefault#system-linq-enumerable-elementatordefault-1(system-collections-generic-ienumerable((-0))-system-index))

 * `IEnumerable Except(IEnumerable, TSource)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.except#system-linq-enumerable-except-1(system-collections-generic-ienumerable((-0))-system-collections-generic-ienumerable((-0))))

 * `IEnumerable Except(IEnumerable, TSource, IEqualityComparer?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.except#system-linq-enumerable-except-1(system-collections-generic-ienumerable((-0))-system-collections-generic-ienumerable((-0))-system-collections-generic-iequalitycomparer((-0))))

 * `IEnumerable Except(IEnumerable, IEqualityComparer, TSource[])` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.except#system-linq-enumerable-except-1(system-collections-generic-ienumerable((-0))-system-collections-generic-ienumerable((-0))-system-collections-generic-iequalitycomparer((-0))))

 * `IEnumerable ExceptBy(IEnumerable, IEnumerable, Func)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.exceptby#system-linq-enumerable-exceptby-2(system-collections-generic-ienumerable((-0))-system-collections-generic-ienumerable((-1))-system-func((-0-1))))

 * `IEnumerable ExceptBy(IEnumerable, IEnumerable, Func, IEqualityComparer?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.exceptby#system-linq-enumerable-exceptby-2(system-collections-generic-ienumerable((-0))-system-collections-generic-ienumerable((-1))-system-func((-0-1))-system-collections-generic-iequalitycomparer((-1))))

 * `TSource FirstOrDefault(IEnumerable, Func, TSource)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.firstordefault#system-linq-enumerable-firstordefault-1(system-collections-generic-ienumerable((-0))-system-func((-0-system-boolean))-0))

 * `TSource FirstOrDefault(IEnumerable, TSource)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.firstordefault#system-linq-enumerable-firstordefault-1(system-collections-generic-ienumerable((-0))-0))

 * `IEnumerable<(int Index, TSource Item)> Index(IEnumerable)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.index#system-linq-enumerable-index-1(system-collections-generic-ienumerable((-0))))

 * `TSource LastOrDefault(IEnumerable, TSource)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.lastordefault#system-linq-enumerable-lastordefault-1(system-collections-generic-ienumerable((-0))-0))

 * `TSource LastOrDefault(IEnumerable, Func, TSource)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.lastordefault#system-linq-enumerable-lastordefault-1(system-collections-generic-ienumerable((-0))-system-func((-0-system-boolean))-0))

 * `TSource? Max(IEnumerable, IComparer?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.max#system-linq-enumerable-max-1(system-collections-generic-ienumerable((-0))-system-collections-generic-icomparer((-0))))

 * `TSource? MaxBy(IEnumerable, Func)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.maxby#system-linq-enumerable-maxby-2(system-collections-generic-ienumerable((-0))-system-func((-0-1))))

 * `TSource? MaxBy(IEnumerable, Func, IComparer?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.maxby#system-linq-enumerable-maxby-2(system-collections-generic-ienumerable((-0))-system-func((-0-1))-system-collections-generic-icomparer((-1))))

 * `TSource? Min(IEnumerable, IComparer?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.min#system-linq-enumerable-min-1(system-collections-generic-ienumerable((-0))-system-collections-generic-icomparer((-0))))

 * `TSource? MinBy(IEnumerable, Func)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.minby#system-linq-enumerable-minby-2(system-collections-generic-ienumerable((-0))-system-func((-0-1))))

 * `TSource? MinBy(IEnumerable, Func, IComparer?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.minby#system-linq-enumerable-minby-2(system-collections-generic-ienumerable((-0))-system-func((-0-1))-system-collections-generic-icomparer((-1))))

 * `TSource SingleOrDefault(IEnumerable, Func, TSource)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.singleordefault#system-linq-enumerable-singleordefault-1(system-collections-generic-ienumerable((-0))-system-func((-0-system-boolean))-0))

 * `TSource SingleOrDefault(IEnumerable, TSource)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.singleordefault#system-linq-enumerable-singleordefault-1(system-collections-generic-ienumerable((-0))-0))

 * `IEnumerable SkipLast(IEnumerable, int)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.skiplast)

 * `IEnumerable Take(IEnumerable, Range)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.take#system-linq-enumerable-take-1(system-collections-generic-ienumerable((-0))-system-range))

 * `IEnumerable TakeLast(IEnumerable, int)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.takelast)

 * `HashSet ToHashSet(IEnumerable, IEqualityComparer?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.tohashset#system-linq-enumerable-tohashset-1(system-collections-generic-ienumerable((-0))-system-collections-generic-iequalitycomparer((-0))))

 * `bool TryGetNonEnumeratedCount(IEnumerable, int)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.linq.enumerable.trygetnonenumeratedcount)

#### IList

 * `ReadOnlyCollection AsReadOnly(IList)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.collectionextensions.asreadonly#system-collections-generic-collectionextensions-asreadonly-1(system-collections-generic-ilist((-0))))

#### int

 * `bool TryFormat(int, Span, int, ReadOnlySpan, IFormatProvider?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.int32.tryformat#system-int32-tryformat(system-span((system-byte))-system-int32@-system-readonlyspan((system-char))-system-iformatprovider))

 * `bool TryFormat(int, Span, int, ReadOnlySpan, IFormatProvider?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.int32.tryformat#system-int32-tryformat(system-span((system-char))-system-int32@-system-readonlyspan((system-char))-system-iformatprovider))

#### IReadOnlyDictionary

 * `TValue? GetValueOrDefault(IReadOnlyDictionary, TKey) where TKey : notnull` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.collectionextensions.getvalueordefault)

 * `TValue GetValueOrDefault(IReadOnlyDictionary, TKey, TValue) where TKey : notnull` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.collectionextensions.getvalueordefault#system-collections-generic-collectionextensions-getvalueordefault-2(system-collections-generic-ireadonlydictionary((-0-1))-0-1))

#### ISet

 * `ReadOnlySet AsReadOnly(ISet)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.collectionextensions.asreadonly#system-collections-generic-collectionextensions-asreadonly-1(system-collections-generic-iset((-0))))

#### KeyValuePair

 * `void Deconstruct(KeyValuePair, TKey, TValue)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.keyvaluepair-2.deconstruct)

#### List

 * `void AddRange(List, ReadOnlySpan)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.collectionextensions.addrange)

 * `void CopyTo(List, Span)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.collectionextensions.copyto)

 * `void EnsureCapacity(List, int)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.list-1.ensurecapacity#system-collections-generic-list-1-ensurecapacity(system-int32))

 * `void InsertRange(List, int, ReadOnlySpan)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.collectionextensions.insertrange)

 * `void TrimExcess(List)`

#### long

 * `bool TryFormat(long, Span, int, ReadOnlySpan, IFormatProvider?)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.int64.tryformat#system-int64-tryformat(system-span((system-byte))-system-int32@-system-readonlyspan((system-char))-system-iformatprovider))

 * `bool TryFormat(long, Span, int, ReadOnlySpan
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