[Lldb-commits] [lldb] [lldb] Adding A new Binding helper for JSONTransport. (PR #159160)

[Jonas Devlieghere via lldb-commits]

================
@@ -297,6 +354,463 @@ class JSONRPCTransport : public IOTransport<Req, Resp, Evt> {
   static constexpr llvm::StringLiteral kMessageSeparator = "\n";
 };
 
-} // namespace lldb_private
+/// A handler for the response to an outgoing request.
+template <typename T>
+using Reply =
+    std::conditional_t<std::is_void_v<T>,
+                       llvm::unique_function<void(llvm::Error)>,
+                       llvm::unique_function<void(llvm::Expected<T>)>>;
+
+namespace detail {
+template <typename R, typename P> struct request_t final {
+  using type = llvm::unique_function<void(const P &, Reply<R>)>;
+};
+template <typename R> struct request_t<R, void> final {
+  using type = llvm::unique_function<void(Reply<R>)>;
+};
+template <typename P> struct event_t final {
+  using type = llvm::unique_function<void(const P &)>;
+};
+template <> struct event_t<void> final {
+  using type = llvm::unique_function<void()>;
+};
+} // namespace detail
+
+template <typename R, typename P>
+using OutgoingRequest = typename detail::request_t<R, P>::type;
+
+/// A function to send an outgoing event.
+template <typename P> using OutgoingEvent = typename detail::event_t<P>::type;
+
+// FIXME: With c++20, we should use this concept:
----------------
JDevlieghere wrote:

I find commented out code really annoying and I strongly prefer putting code behind `#if 0`. Or even better, if it compiles with C++20 support, we could gate this by `#if __cplusplus >= 202002L`. 

https://github.com/llvm/llvm-project/pull/159160