使用非标准语言功能编译C#

Question

我需要将用户类型的表达式编译成可以调用的.NET程序集.表达式语言(从应用程序的版本1继承)非常有限,几乎是有效的C#,但它确实有一些不寻常的属性.

我想在版本2中切换到完整的C#,但是我在使用Roslyn将特性转换为可编译的SyntaxTree时遇到了麻烦.目前我正试图弄清楚如何获得权力和因子来编译,即

double n = 1.5² / 0.9³ + 6!;

必须转换成类似的东西:

double n = Pow(1.5, 2) / Pow(0.9, 3) + Factorial(6);

但是,当我解析原始表达式时,它会立即在²字符处分解:

public static void TestLanguageAdditions()
{
  const string code = "double n = 1.5² / 0.9³ + 6!;";

  var syntaxTree = CSharpSyntaxTree.ParseText(code);
  var syntaxRoot = syntaxTree.GetRoot();

  var sb = new StringBuilder();
  sb.AppendLine(code);
  sb.AppendLine();

  foreach (var node in syntaxRoot.DescendantNodes())
  {
    var span = node.FullSpan;
    var spanLine = 
      new string(' ', span.Start) + 
      new string('?', span.Length);

    spanLine = spanLine.PadRight(30);
    spanLine += ((CSharpSyntaxNode)node).Kind();

    sb.AppendLine(spanLine);
  }

  string report = sb.ToString();
  Console.Write(report);
}

产量:

double n = 1.5² / 0.9³ + 6!;

????????????????????????????  FieldDeclaration
??????????????                VariableDeclaration
???????                       PredefinedType
       ???????                VariableDeclarator
         ?????                EqualsValueClause
           ???                NumericLiteralExpression

我想知道是否有任何方法可以哄骗Roslyn按原样解析其余的字符串,或者如果没有,那么准备字符串的好策略是什么.显然我可以用一些可解析的占位符替换²和³字符,但不能在字符串或字符文字中出现这些字符时.

-----------------------------------编辑-------------- ---------------------

将非法字符转换为块注释允许解析,但奇怪的是它们在许多节点之后显示为琐事:

double n = 1.50/*²*/ / (0.90)/*³*/ + 6/*!*/;
???????????????????????????????????????????? CompilationUnit
???????????????????????????????????????????? FieldDeclaration
???????????????????????????????????????????· VariableDeclaration
······································?????·  ? trivia: /*!*/
???????····································· PredefinedType
·······????????????????????????????????????· VariableDeclarator
······································?????·  ? trivia: /*!*/
·········??????????????????????????????????· EqualsValueClause
······································?????·  ? trivia: /*!*/
···········????????????????????????????????· AddExpression
······································?????·  ? trivia: /*!*/
···········????????????????????????········· DivideExpression
·····························?????··········  ? trivia: /*³*/
···········??????????······················· NumericLiteralExpression
···············?????························  ? trivia: /*²*/
·······················????????????········· ParenthesizedExpression
·····························?????··········  ? trivia: /*³*/
························????················ NumericLiteralExpression
·····································??????· NumericLiteralExpression
······································?????·  ? trivia: /*!*/