Unity Playworks Plugin Compiler V2

Playworks Plugin now has support of C# 8.0 and C# 9.0 features. This option is disabled by default and could be activated in Playworks Plugin Plugin window.

When to use?

If you know, that you use C# 8.0 or C# 9.0 features in project - enabling of Unity Playworks Plugin Compiler v2 is recommended.

Popular C# 8.0 and C# 9.0 features:

• Pattern matching

if(fruit is Apple)
{
  MakeApplePieFrom(fruit as Apple);
}

• Using declarations

static int WriteLinesToFile(IEnumerable<string> lines)
{
    using var file = new System.IO.StreamWriter("WriteLines2.txt");
    int skippedLines = 0;
    foreach (string line in lines)
    {
        if (!line.Contains("Second"))
        {
            file.WriteLine(line);
        }
        else
        {
            skippedLines++;
        }
    }
    // Notice how skippedLines is in scope here.
    return skippedLines;
    // file is disposed here
}

• Null-coalescing assignment

List<int> numbers = null;
int? i = null;

numbers ??= new List<int>();
numbers.Add(i ??= 17);
numbers.Add(i ??= 20);

Console.WriteLine(string.Join(" ", numbers));  // output: 17 17
Console.WriteLine(i);  // output: 17

• Enhancement of interpolated verbatim strings

var myString1 = $@"...";
var myString2 = @$"...";

If you see errors on Unity Playworks Plugin Compiler v1 (default compiler), then enabling of Unity Playworks Plugin Compiler v2 could solve the issue:

• Feature is not available in C# 7.0. Please use language version 8.0 or greater.
• An expression of type MyCustomType cannot be handled by a pattern of type “not null” in C# 8.0. Please use language version 9.0 or greater.
• Tuple element name MyElementName is inferred. Please use language version 9.0 or greater to access an element by its inferred name.
• Invalid MyCustomType value: null for C# 8.0. Please use language version 9.0 or greater.

Supported Unity versions

Option is not available on Unity 2019.X - 2020.1.

C# 8.0 works on Unity 2020.2 or higher.

C# 9.0 works on Unity 2021.2 or higher.

Tools

Unity Playworks Plugin Compiler v2 uses Mono Runtime, MSBuild and Roslyn compiler directly from Unity Editor installation, so no additional tools required.

How it affects your playable?

• With Unity Playworks Plugin Compiler v2 you could use newest C# features.
• With Unity Playworks Plugin Compiler v2 build time slightly increased.
• With Unity Playworks Plugin Compiler v2 all Unity Playworks Plugin types now arent exposed to user (see Caveats section for more details).

Supported features

Playworks Plugin Plugin supports almost all C# 9.0 features, which Unity supports. Full list of tested features you could find below:

C# 8.0 Features

Feature	Support
Null-coalescing assignment	Supported
Pattern-matching enhancements	Supported
Readonly members	Supported
Static local functions	Supported
Using declarations	Supported
Enhancement of interpolated verbatim strings	Supported
Disposable ref structs	Unsupported
Stackalloc in nested expressions	Unsupported
Unmanaged constructed types	Unsupported
Default interface methods	Unsupported (Unity does not support)
Indices and ranges	Unsupported (Unity does not support)
Asynchronous streams	Unsupported (Unity does not support)
Asynchronous disposable	Unsupported (Unity does not support)

C# 9.0 Features

Feature	Support
Lambda discard parameters	Supported
Target-typed new	Supported
Pattern-matching enhancements	Supported
Static anonymous functions	Supported
Lambda discard parameters	Supported
Target-typed conditional expression	Unsupported
Local function attribute	Unsupported
Native-sized integers	Unsupported
Skip localsinit	Unsupported
Records	Unsupported
Init-only setters	Unsupported (Unity does not support)
Covariant returns	Unsupported (Unity does not support)
Top-level statements	Unsupported
Function Pointers	Unsupported (Unity does not support)

Caveats

Unity Playworks Plugin specific types

In some rare cases, your code could use Playworks Plugin Plugin internal classes (due to custom package or any kind of custom changes in your project) such as ElementComponent class, so, it could not be exposed as public anymore. Such issues have workarounds, you could ask for help from our support.