⚠️ NOTE: Do not use the obsolete tags and branches to reference the package. They will be removed in near future. ⚠️

Change the C# compiler (csc) used on your Unity project, as you like!

<< Description | Installation | Usage | Contributing >>

A good news! Unity 2020.2.0a12 or later now supports C# 8.0!

Many developers (including you!) have been eagerly awaiting support for C# 8.0.
C# 8.0 includes some features and some useful syntax-sugars:

• Readonly members
• Default interface methods
• Pattern matching enhancements:
  • Switch expressions
  • Property patterns
  • Tuple patterns
  • Positional patterns
• Using declarations
• Static local functions
• Disposable ref structs
• Nullable reference types
• Asynchronous streams
• Asynchronous disposable
• Indices and ranges
• Null-coalescing assignment
• Unmanaged constructed types
• Stackalloc in nested expressions
• Enhancement of interpolated verbatim strings

However, unfortunately, there are no plans to backport to Unity 2020.1 or earlier...

This package changes the C# compiler (csc) used on your Unity project, to support C# 8.0.
Let's enjoy C# 8.0 features with your Unity project!

• Easy to use.
  • This package is out of the box!
• Change the C# compiler (csc) used on your Unity project.
  • Change the nuget package name.
    • Microsoft.Net.Compilers: Official compiler (default, run on Unity built-in mono)
    • Microsoft.Net.Compilers.Toolset: Official compiler (run on dotnet)
      • Resolve the issue #2
    • OpenSesame.Net.Compilers: Allows access to internals/privates in other assemblies (run on Unity built-in mono)
    • OpenSesame.Net.Compilers.Toolset: Allows access to internals/privates in other assemblies (run on dotnet)
      • Resolve the issue #2
    • Or, your custom nuget package
  • Change the nuget package version.
    • 3.4.0: C# 8.0 Supported.
    • 3.5.0: C# 8.0 Supported. (default in Unity 2020.2.0)
    • 3.6.0: C# 8.0 Supported.
    • 3.7.0: C# 8.0 Supported.
    • 3.8.0 (preview): C# 9.0 Supported.
    • For other versions, see the nuget package page above.
  • Change the C# language version.
    • 7.0
    • 7.1
    • 7.2
    • 7.3
    • 8.0 (latest, default in Unity 2020.2.0)
    • 9.0 (preview)
• Add the scripting define symbols based on language version on compiling.
  • e.g. CSHARP_7_3_OR_LATER, CSHARP_8_OR_LATER, CSHARP_9_OR_LATER
• Change the C# compiler settings for each *.asmdef file.
  • Portability: The assembly works even in the projects that do not have this package installed.
    • The best option when distributing as a package.
  • Publish as Dll: Published dll works without this package.
  • Modify the scripting define symbols for each *.asmdef file.
    • Add/Remove specific symbols separated with semicolons (';') or commas (',').
    • The symbols starting with '!' will be removed.
    • e.g. SYMBOL_TO_ADD;!SYMBOL_TO_REMOVE;...
• Modify langversion property in *.csproj file.
• If dotnet is required, install it automatically.
• CompilerType.BuiltIn compiler option to disable this plugin.
• Enable Logging option to display compilation log.
• Nullable option to enable Nullable reference types (C# 8.0).
  • enable: The nullable annotation context is enabled. The nullable warning context is enabled.
    • Variables of a reference type, string for example, are non-nullable. All nullability warnings are enabled.
  • warnings: The nullable annotation context is disabled. The nullable warning context is enabled.
    • Variables of a reference type are oblivious. All nullability warnings are enabled.
  • annotations: The nullable annotation context is enabled. The nullable warning context is disabled.
    • Variables of a reference type, string for example, are non-nullable. All nullability warnings are disabled.
  • disable: The nullable annotation context is disabled. The nullable warning context is disabled.
    • Variables of a reference type are oblivious, just like earlier versions of C#. All nullability warnings are disabled.
• Analyzer option to analyze your code on compile.

• Add a dropdown menu to select version.
• Verify the selected pakcage name and version.
• Show package description.

https://forum.unity.com/threads/unity-c-8-support.663757/page-2#post-5738029

Unity doesn't support using your own C# compiler. While this is possible, it is not something I would recommend, as we've not tested customer C# compiler versions with Unity.

• Unity 2018.3 or later

This package is available on OpenUPM.
After installing openupm-cli, run the following command

openupm add com.coffee.csharp-compiler-settings

Find the manifest.json file in the Packages directory in your project and edit it to look like this:

{
  "dependencies": {
    "com.coffee.csharp-compiler-settings": "https://github.com/mob-sakai/CSharpCompilerSettingsForUnity.git",
    ...
  },
}

To update the package, change suffix #{version} to the target version.

• e.g. "com.coffee.csharp-compiler-settings": "https://github.com/mob-sakai/CSharpCompilerSettingsForUnity.git#1.0.0",

Or, use UpmGitExtension to install and update the package.

1. Open project setting window. (Edit > Project Settings)
   
2. Select C# Compiler tab
3. Set Compiler Type to Custom Package, to use custom compiler package.
   
4. Input Package Name, Package Version, Language Version for compilation.
   • See features section.
5. Press Apply button to save settings.
6. It will automatically request a recompilation.
   The selected nuget package will be used for compilation.
7. Enjoy!

The project setting asset for C# Compiler will be saved in ProjectSettings/CSharpCompilerSettings.asset.

{
    "m_UseDefaultCompiler": false,
    "m_Version": 110,
    "m_CompilerType": 1,
    "m_PackageName": "Microsoft.Net.Compilers.Toolset",
    "m_PackageVersion": "3.8.0-3.final",
    "m_LanguageVersion": 2147483646,
    "m_EnableLogging": true,
    "m_ModifySymbols": ""
}

1. Select a *.asmodef file
2. Turn on Enable C# Compilier Settings to configure.
   
3. Set Compiler Type to Custom Package, to use custom compiler package.
4. Input Package Name, Package Version, Language Version and Modify Symbols for compilation.
   • See features section.
5. Press Apply button to save settings.

Reload: Reload C# compiler settings dll for the assembly.
Publish as dll: Publish the assembly as dll to the parent directory.

C# 8.0 features
samples

If you want to use the C# 8.0 features, set it up as follows:

• Package Name: Microsoft.Net.Compilers
• Package Version: 3.5.0 or later
• Language Version: latest or CSharp_8

Some features required external library.

• Async stream -> UniTask v2
  • Install to project.
• Indices and ranges -> IndexRange
  • Download nuget package and extract it.
  • Import lib/netstandard2.0/IndexRange.dll to project.
• Stackalloc in nested expressions -> System.Memory
  • Download nuget package and extract it.
  • Import lib/netstandard2.0/System.Memory.dll to project.

NOTE: Default interface methods feature is not available. It requires .Net Standard 2.1.

C# 9.0 features
samples

If you want to use the C# 9.0 features, set it up as follows:

• Package Name: Microsoft.Net.Compilers
• Package Version: 3.8.0-2.final or later
• Language Version: preview

NOTE: Some features is not available. It requires .Net 5.

Issues are very valuable to this project.

• Ideas are a valuable source of contributions others can make
• Problems show where this project is lacking
• With a question you show where contributors can improve the user experience

Pull requests are, a great way to get your ideas into this repository.
See CONTRIBUTING.md and sandbox branch.

This is an open source project that I am developing in my spare time.
If you like it, please support me.
With your support, I can spend more time on development. :)

• MIT

• mob-sakai

• GitHub page : https://github.com/mob-sakai/CSharpCompilerSettingsForUnity
• Releases : https://github.com/mob-sakai/CSharpCompilerSettingsForUnity/releases
• Issue tracker : https://github.com/mob-sakai/CSharpCompilerSettingsForUnity/issues
• Change log : https://github.com/mob-sakai/CSharpCompilerSettingsForUnity/blob/master/CHANGELOG.md
• Test Space : https://mob-sakai.testspace.com/spaces/130862/current