public static void ThrowIfSymbolTableNotSet(this IAstSymbolTableSite symbolTableSite)
 {
     if (symbolTableSite.SymbolTable is null)
     {
         throw new InternalErrorException("Symbol Table was not set.");
     }
 }
 public static AstSymbol AddSymbol(this IAstSymbolTableSite symbolTableSite, string symbolName, AstSymbolKind kind, AstNode?node = null)
 => symbolTableSite.SymbolTable.AddSymbol(symbolName, kind, node);