work around various gcc-6 and -7 bugs

fbshipit-source-id: a26e4e767b4aea27d5092edba3f755a02a8e1cbe

folly/experimental/pushmi/include/pushmi.h

@@ -920,7 +920,7 @@ PUSHMI_CONCEPT_DEF(
     Semiregular<T> && EqualityComparable<T>
 );
 
-#if __cpp_lib_invoke >= 201411
+#if 0 //__cpp_lib_invoke >= 201411
 using std::invoke;
 #else
 PUSHMI_TEMPLATE (class F, class...As)
@@ -5080,9 +5080,21 @@ struct out_from_fn {
 };
 
 PUSHMI_TEMPLATE(class In, class FN)
-  (requires Sender<In> && SemiMovable<FN>)
+  (requires Sender<In> && SemiMovable<FN>
+    PUSHMI_BROKEN_SUBSUMPTION(&& not TimeSender<In>))
+auto submit_transform_out(FN fn){
+  return on_submit(
+    constrain(lazy::Receiver<_2>,
+      [fn = std::move(fn)](In& in, auto out) {
+        ::pushmi::submit(in, fn(std::move(out)));
+      }
+    )
+  );
+}
+
+PUSHMI_TEMPLATE(class In, class FN)
+  (requires TimeSender<In> && SemiMovable<FN>)
 auto submit_transform_out(FN fn){
-  PUSHMI_IF_CONSTEXPR_RETURN( ((bool) TimeSender<In>) (
   return on_submit(
     constrain(lazy::Receiver<_3>,
       [fn = std::move(fn)](In& in, auto tp, auto out) {
@@ -5090,21 +5102,24 @@ auto submit_transform_out(FN fn){
       }
     )
   );
-  ) else (
+}
+
+PUSHMI_TEMPLATE(class In, class SDSF, class TSDSF)
+  (requires Sender<In> && SemiMovable<SDSF> && SemiMovable<TSDSF>
+    PUSHMI_BROKEN_SUBSUMPTION(&& not TimeSender<In>))
+auto submit_transform_out(SDSF sdsf, TSDSF tsdsf) {
   return on_submit(
-      constrain(lazy::Receiver<_2>,
-        [fn = std::move(fn)](In& in, auto out) {
-          ::pushmi::submit(in, fn(std::move(out)));
+    constrain(lazy::Receiver<_2> && lazy::Invocable<SDSF&, In&, _2>,
+      [sdsf = std::move(sdsf)](In& in, auto out) {
+        sdsf(in, std::move(out));
       }
     )
   );
-  ))
 }
 
 PUSHMI_TEMPLATE(class In, class SDSF, class TSDSF)
-  (requires Sender<In> && SemiMovable<SDSF> && SemiMovable<TSDSF>)
+  (requires TimeSender<In> && SemiMovable<SDSF> && SemiMovable<TSDSF>)
 auto submit_transform_out(SDSF sdsf, TSDSF tsdsf) {
-  PUSHMI_IF_CONSTEXPR_RETURN( ((bool) TimeSender<In>) (
   return on_submit(
     constrain(lazy::Receiver<_3> && lazy::Invocable<TSDSF&, In&, _2, _3>,
       [tsdsf = std::move(tsdsf)](In& in, auto tp, auto out) {
@@ -5112,15 +5127,6 @@ auto submit_transform_out(SDSF sdsf, TSDSF tsdsf) {
       }
     )
   );
-  ) else (
-    return on_submit(
-      constrain(lazy::Receiver<_2> && lazy::Invocable<SDSF&, In&, _2>,
-        [sdsf = std::move(sdsf)](In& in, auto out) {
-          sdsf(in, std::move(out));
-        }
-      )
-    );
-  ))
 }
 
 PUSHMI_TEMPLATE(class In, class Out)
@@ -6020,6 +6026,10 @@ PUSHMI_INLINE_VAR constexpr struct make_tap_fn {
 } const make_tap {};
 
 struct tap_fn {
+private:
+  template <class In, class SideEffects>
+  static auto impl(In, SideEffects);
+public:
   template <class... AN>
   auto operator()(AN... an) const;
 };
@@ -6040,9 +6050,14 @@ auto tap_fn::operator()(AN... an) const {
   return constrain(lazy::Sender<_1>,
     [args = std::tuple<AN...>{std::move(an)...}](auto in) mutable {
       using In = decltype(in);
-      auto sideEffects{::pushmi::detail::out_from_fn<In>()(std::move(args))};
-      using SideEffects = decltype(sideEffects);
+      return tap_fn::impl(
+        std::move(in),
+        ::pushmi::detail::out_from_fn<In>()(std::move(args)));
+    });
+}
 
+template <class In, class SideEffects>
+auto tap_fn::impl(In in, SideEffects sideEffects) {
   PUSHMI_STATIC_ASSERT(
     ::pushmi::detail::deferred_requires_from<In, SideEffects,
       SenderTo<In, SideEffects, is_none<>>,
@@ -6076,8 +6091,6 @@ auto tap_fn::operator()(AN... an) const {
       )
     )
   );
-    }
-  );
 }
 
 } // namespace detail

folly/experimental/pushmi/include/pushmi/o/extension_operators.h

@@ -81,9 +81,21 @@ struct out_from_fn {
 };
 
 PUSHMI_TEMPLATE(class In, class FN)
-  (requires Sender<In> && SemiMovable<FN>)
+  (requires Sender<In> && SemiMovable<FN>
+    PUSHMI_BROKEN_SUBSUMPTION(&& not TimeSender<In>))
+auto submit_transform_out(FN fn){
+  return on_submit(
+    constrain(lazy::Receiver<_2>,
+      [fn = std::move(fn)](In& in, auto out) {
+        ::pushmi::submit(in, fn(std::move(out)));
+      }
+    )
+  );
+}
+
+PUSHMI_TEMPLATE(class In, class FN)
+  (requires TimeSender<In> && SemiMovable<FN>)
 auto submit_transform_out(FN fn){
-  PUSHMI_IF_CONSTEXPR_RETURN( ((bool) TimeSender<In>) (
   return on_submit(
     constrain(lazy::Receiver<_3>,
       [fn = std::move(fn)](In& in, auto tp, auto out) {
@@ -91,21 +103,24 @@ auto submit_transform_out(FN fn){
       }
     )
   );
-  ) else (
+}
+
+PUSHMI_TEMPLATE(class In, class SDSF, class TSDSF)
+  (requires Sender<In> && SemiMovable<SDSF> && SemiMovable<TSDSF>
+    PUSHMI_BROKEN_SUBSUMPTION(&& not TimeSender<In>))
+auto submit_transform_out(SDSF sdsf, TSDSF tsdsf) {
   return on_submit(
-      constrain(lazy::Receiver<_2>,
-        [fn = std::move(fn)](In& in, auto out) {
-          ::pushmi::submit(in, fn(std::move(out)));
+    constrain(lazy::Receiver<_2> && lazy::Invocable<SDSF&, In&, _2>,
+      [sdsf = std::move(sdsf)](In& in, auto out) {
+        sdsf(in, std::move(out));
       }
     )
   );
-  ))
 }
 
 PUSHMI_TEMPLATE(class In, class SDSF, class TSDSF)
-  (requires Sender<In> && SemiMovable<SDSF> && SemiMovable<TSDSF>)
+  (requires TimeSender<In> && SemiMovable<SDSF> && SemiMovable<TSDSF>)
 auto submit_transform_out(SDSF sdsf, TSDSF tsdsf) {
-  PUSHMI_IF_CONSTEXPR_RETURN( ((bool) TimeSender<In>) (
   return on_submit(
     constrain(lazy::Receiver<_3> && lazy::Invocable<TSDSF&, In&, _2, _3>,
       [tsdsf = std::move(tsdsf)](In& in, auto tp, auto out) {
@@ -113,15 +128,6 @@ auto submit_transform_out(SDSF sdsf, TSDSF tsdsf) {
       }
     )
   );
-  ) else (
-    return on_submit(
-      constrain(lazy::Receiver<_2> && lazy::Invocable<SDSF&, In&, _2>,
-        [sdsf = std::move(sdsf)](In& in, auto out) {
-          sdsf(in, std::move(out));
-        }
-      )
-    );
-  ))
 }
 
 PUSHMI_TEMPLATE(class In, class Out)

folly/experimental/pushmi/include/pushmi/o/tap.h

@@ -57,6 +57,10 @@ PUSHMI_INLINE_VAR constexpr struct make_tap_fn {
 } const make_tap {};
 
 struct tap_fn {
+private:
+  template <class In, class SideEffects>
+  static auto impl(In, SideEffects);
+public:
   template <class... AN>
   auto operator()(AN... an) const;
 };
@@ -77,9 +81,14 @@ auto tap_fn::operator()(AN... an) const {
   return constrain(lazy::Sender<_1>,
     [args = std::tuple<AN...>{std::move(an)...}](auto in) mutable {
       using In = decltype(in);
-      auto sideEffects{::pushmi::detail::out_from_fn<In>()(std::move(args))};
-      using SideEffects = decltype(sideEffects);
+      return tap_fn::impl(
+        std::move(in),
+        ::pushmi::detail::out_from_fn<In>()(std::move(args)));
+    });
+}
 
+template <class In, class SideEffects>
+auto tap_fn::impl(In in, SideEffects sideEffects) {
   PUSHMI_STATIC_ASSERT(
     ::pushmi::detail::deferred_requires_from<In, SideEffects,
       SenderTo<In, SideEffects, is_none<>>,
@@ -113,8 +122,6 @@ auto tap_fn::operator()(AN... an) const {
       )
     )
   );
-    }
-  );
 }
 
 } // namespace detail

folly/experimental/pushmi/include/pushmi/traits.h

@@ -192,7 +192,7 @@ PUSHMI_CONCEPT_DEF(
     Semiregular<T> && EqualityComparable<T>
 );
 
-#if __cpp_lib_invoke >= 201411
+#if 0 //__cpp_lib_invoke >= 201411
 using std::invoke;
 #else
 PUSHMI_TEMPLATE (class F, class...As)