A polyfill-like package that is focused on making it easier to work around missing features, rather than provide hacky attempts at implementing them. The main purpose of this is to make it easier to write multi-targeting libraries.

An example of the spirit of this library is the CallerArgumentExpressionAttribute, under normal usage, the compiler provides the expression that was passed in for a different parameter as a string, some polyfill libraries try to imitate that behaviour, however this library will only provide a replica of the attribute class in order to make multi-targeting easier.

To use this package download the latest release files, and add them to a local NuGet feed, after that you can reference it from your .NET project. An official nuget.org package will be released at a later point in time.

In C#, that would look like this:

<ItemGroup>
  <PackageReference Include="OwlDomain.Polyease" Version="1.1.0" />
</ItemGroup>

For the best results, use multi-targeting in your project, and then use conditional expressions to ensure that the package is only referenced when necessary.

In C#, that would look like this:

<PropertyGroup>
  <TargetFrameworks>netstandard2.1; net7.0</TargetFrameworks>
</PropertyGroup>

<ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.1'">
  <PackageReference Include="OwlDomain.Polyease" Version="1.1.0" />
</ItemGroup>

The reason for this is that if you wanted to use the UnreachableException in your library code, and you were multi-targeting .NET Standard 2.1 and .NET 7, then when your library was being used under .NET Standard 2.1 the OwlDomain.Polyease package would become a dependency and would be required by your package, however if your library was being used under .NET 7 then the OwlDomain.Polyease package would not be referenced, and therefore it would never be a dependency.

The conditional expressions are not strictly necessary for the package to work, as the OwlDomain.Polyease package uses conditional compilation to ensure that the poly-eased features are only present when they are missing. However using the conditional expressions helps to keep your dependencies clean.

To use this package in your code, simply reference it, nothing else specific has to be done in order to use it, as the poly-eased features are placed in the same namespaces as the official versions.

• UnreachableException - officially available in .NET 7.0/later.
• CallerArgumentExpressionAttribute - officially available in .NET Core 3.0/later and .NET 5.0/later.
• StringSyntaxAttribute - officially available in .NET 7.0/later.

Code contributions will not be accepted, however feel free to provide feedback / suggestions by creating a new issue, or look at the existing issues to see if your concern / suggestion has already been raised.

This project (the source, and the release files, e.t.c) are not currently under any license, all rights are reserved, however it will become more permissive at a later date.

Parts of this project are copied / derived under the MIT license from the .NET Foundation and Contributors, you can read their full license here.