Some informations exist;
- https://docs.microsoft.com/en-us/windows-server/identity/solution-guides/claims-transformation-rules-language
- https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2008-R2-and-2008/dd807118(v=ws.10)
Here is a usage example;
//Setup (this can be done once)
var parser = new ClaimsTransformationParser();
var cache = new ClaimsTransformationCache();
var engine = new ClaimsTransformationEngine(parser, cache);
var expression =
@"C1:[] " +
@"=> ISSUE(TYPE = ""http://namespace/role"", VALUE = ""Public"");";
//Read these claims from your authentication token.
var input = new Claim[] { };
//Use these claims for your security.
var output = engine.Transform(expression, input);
See the test suite for more examples.