Tidy the view serializer: doxygen block placement, enabled() for a constant

Signed-off-by: Niels Lohmann <mail@nlohmann.me>

include/nlohmann/detail/view/serializer.hpp

@@ -357,16 +357,6 @@ class view_serializer
     }
 
   private:
-    /*!
-    @brief the compact output without ensure_ascii (the default dump())
-
-    The same walk as dump(), with the write position in a local variable
-    (stores through char pointers would otherwise force a reload of the
-    buffer's members after each one), and with strings and number tokens of
-    the source copied by fixed-size moves of 32 bytes where the source has
-    that many bytes left, instead of a library call per token. The buffer
-    keeps 64 bytes of slack for the overshoot.
-    */
     /// a string that is not a plain string of the source (decoded, or written
     /// by an edit), without ensure_ascii: runs without characters to escape
     /// are copied
@@ -405,6 +395,16 @@ class view_serializer
         return option;
     }
 
+    /*!
+    @brief the compact output without ensure_ascii (the default dump())
+
+    The same walk as dump(), with the write position in a local variable
+    (stores through char pointers would otherwise force a reload of the
+    buffer's members after each one), and with strings and number tokens of
+    the source copied by fixed-size moves of 32 bytes where the source has
+    that many bytes left, instead of a library call per token. The buffer
+    keeps 64 bytes of slack for the overshoot.
+    */
     template<bool SourceNumbers>
     void dump_compact(const node* root)
     {
@@ -526,7 +526,7 @@ class view_serializer
                         room(n->len);
                         copy(src + n->off, n->len);
                     }
-                    else if (std::is_same<number_float_t, double>::value)
+                    else if (enabled(std::is_same<number_float_t, double>::value))
                     {
                         room(64);
                         w = write_double_at(w, *n);