switch to v2.4.0

diagnose.cabal

@@ -5,7 +5,7 @@ cabal-version: 1.12
 -- see: https://github.com/sol/hpack
 
 name:           diagnose
-version:        2.3.1
+version:        2.4.0
 synopsis:       Beautiful error reporting done easily
 description:    This package provides a simple way of getting beautiful compiler/interpreter errors
                 using a very simple interface for the programmer.

package.yaml

@@ -1,5 +1,5 @@
 name: diagnose
-version: 2.3.1
+version: 2.4.0
 github: "mesabloo/diagnose"
 license: BSD3
 author: "Ghilain Bergeron"

src/Error/Diagnose/Report/Internal.hs

@@ -107,6 +107,7 @@ instance ToJSON msg => ToJSON (Report msg) where
                    Maybe m -> [ "message" .= m
                               , "kind" .= ("maybe" :: String)
                               ]
+                   Blank -> [ "kind" .= ("blank" :: String) ]
 #endif
 
 -- | The type of markers with abstract message type, shown under code lines.