Reimplement folly::Function to improve compile times.

[folly.git] / folly / ExceptionWrapper.h

diff --git a/folly/ExceptionWrapper.h b/folly/ExceptionWrapper.h
index 70eb996bd433a7c906267492aa77471db6dc4c68..22857a0b9b543259f504e52dc9283b9bf023db52 100644 (file)
--- a/folly/ExceptionWrapper.h
+++ b/folly/ExceptionWrapper.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 Facebook, Inc.
+ * Copyright 2016 Facebook, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef FOLLY_EXCEPTIONWRAPPER_H
-#define FOLLY_EXCEPTIONWRAPPER_H
+#pragma once
 
 #include <cassert>
 #include <exception>
@@ -88,16 +87,15 @@ namespace folly {
  *
  * // Thread2: Exceptions are bad!
  * void processResult() {
- *   auto ep = globalExceptionWrapper.get();
- *   if (!ep.with_exception<FacePlantException>([&](
- *     FacePlantException& faceplant) {
- *       LOG(ERROR) << "FACEPLANT";
- *     })) {
- *     ep.with_exception<FailWhaleException>([&](
- *       FailWhaleException& failwhale) {
+ *   globalExceptionWrapper.with_exception(
+ *       [&](FacePlantException& faceplant) {
+ *         LOG(ERROR) << "FACEPLANT";
+ *       }) ||
+ *   globalExceptionWrapper.with_exception(
+ *       [&](FailWhaleException& failwhale) {
  *         LOG(ERROR) << "FAILWHALE!";
- *       });
- *   }
+ *       }) ||
+ *   LOG(FATAL) << "Unrecognized exception";
  * }
  *
  */
@@ -330,7 +328,9 @@ private:
     struct impl<R(C::*)(A)> { using arg_type = A; };
     template <typename C, typename R, typename A>
     struct impl<R(C::*)(A) const> { using arg_type = A; };
-    using arg_type = typename impl<decltype(&F::operator())>::arg_type;
+    using functor_decayed = typename std::decay<F>::type;
+    using functor_op = decltype(&functor_decayed::operator());
+    using arg_type = typename impl<functor_op>::arg_type;
     using arg_type_decayed = typename std::decay<arg_type>::type;
   };
 
@@ -467,4 +467,3 @@ class try_and_catch<> : public exception_wrapper {
   }
 };
 }
-#endif