workaround boost.span non-SFINAE friendly constructor

revert when boostorg/core#203 gets merged

Author: ashtum

include/boost/http_proto/impl/sink.hpp

@@ -58,9 +58,11 @@ write_impl(
         while(
             p != tmp_end &&
             it != end_);
-        rv += on_write(boost::span<
-            buffers::const_buffer const>(
-                tmp, p - tmp),
+        rv += on_write(
+            true,
+            boost::span<
+                buffers::const_buffer const>(
+                    tmp, p - tmp),
             it != end_ || more);
         if(rv.ec.failed())
             return rv;

include/boost/http_proto/impl/source.hpp

@@ -58,9 +58,11 @@ read_impl(
         while(
             p != tmp_end &&
             it != end_);
-        rv += on_read(boost::span<
-            buffers::mutable_buffer const>(
-                tmp, p - tmp));
+        rv += on_read(
+            true,
+            boost::span<
+                buffers::mutable_buffer const>(
+                    tmp, p - tmp));
         if(rv.ec.failed())
             return rv;
         if(rv.finished)

include/boost/http_proto/sink.hpp

@@ -192,6 +192,7 @@ struct BOOST_SYMBOL_VISIBLE
     virtual
     results
     on_write(
+        bool boost_span_issue_202_workaround,
         boost::span<const buffers::const_buffer> bs,
         bool more);
 
@@ -212,13 +213,13 @@ struct BOOST_SYMBOL_VISIBLE
         return on_write(b, more);
     }
 
-    results
-    write_impl(
-        boost::span<const buffers::const_buffer> const& bs,
-        bool more)
-    {
-        return on_write(bs, more);
-    }
+    // results
+    // write_impl(
+    //     boost::span<const buffers::const_buffer> const& bs,
+    //     bool more)
+    // {
+    //     return on_write(bs, more);
+    // }
 
     template<class T>
     results

include/boost/http_proto/source.hpp

@@ -195,6 +195,7 @@ struct BOOST_SYMBOL_VISIBLE
     virtual
     results
     on_read(
+        bool boost_span_issue_202_workaround,
         boost::span<buffers::mutable_buffer const> bs);
 
 private:
@@ -205,12 +206,12 @@ struct BOOST_SYMBOL_VISIBLE
         return on_read(b);
     }
 
-    results
-    read_impl(
-        boost::span<buffers::mutable_buffer const> const& bs)
-    {
-        return on_read(bs);
-    }
+    // results
+    // read_impl(
+    //     boost::span<buffers::mutable_buffer const> const& bs)
+    // {
+    //     return on_read(bs);
+    // }
 
     template<class T>
     results

src/sink.cpp

@@ -15,6 +15,7 @@ namespace http_proto {
 auto
 sink::
 on_write(
+    bool,
     boost::span<buffers::const_buffer const> bs,
     bool more) ->
         results

src/source.cpp

@@ -16,6 +16,7 @@ namespace http_proto {
 auto
 source::
 on_read(
+    bool,
     boost::span<buffers::mutable_buffer const> bs) ->
         results
 {