Handle MSVC in FBString.h

Summary: Specifically, MSVC doesn't define `std::__ostream_insert`, so just write to the stream instead.
Closes #270

Reviewed By: @yfeldblum

Differential Revision: D2283960

Pulled By: @sgolemon

diff --git a/folly/FBString.h b/folly/FBString.h
index 53ade9b7adad45e333f3f26bb639436974c143aa..4afce748d8bc9d433dc45439f7443da0fd6a435a 100644 (file)
--- a/folly/FBString.h
+++ b/folly/FBString.h
@@ -2370,6 +2370,9 @@ operator<<(
       os.setstate(std::ios_base::badbit | std::ios_base::failbit);
     }
   }
+#elif defined(_MSC_VER)
+  // MSVC doesn't define __ostream_insert
+  os.write(str.data(), str.size());
 #else
   std::__ostream_insert(os, str.data(), str.size());
 #endif