Muse reader: parse "~~" as non-breaking space in Emacs mode

src/Text/Pandoc/Readers/Muse.hs

@@ -581,6 +581,7 @@ inlineList = [ endline
              , subscriptTag
              , strikeoutTag
              , verbatimTag
+             , nbsp
              , link
              , code
              , codeTag
@@ -682,6 +683,12 @@ verbatimTag = do
   content <- parseHtmlContent "verbatim" anyChar
   return $ return $ B.text content
 
+nbsp :: PandocMonad m => MuseParser m (F Inlines)
+nbsp = do
+  guardDisabled Ext_amuse -- Supported only by Emacs Muse
+  string "~~"
+  return $ return $ B.str "\160"
+
 code :: PandocMonad m => MuseParser m (F Inlines)
 code = try $ do
   pos <- getPosition

test/Tests/Readers/Muse.hs

@@ -105,6 +105,9 @@ tests =
 
       , "Linebreak" =: "Line <br>  break" =?> para ("Line" <> linebreak <> "break")
 
+      , test emacsMuse "Non-breaking space"
+        ("Foo~~bar" =?> para ("Foo\160bar"))
+
       , testGroup "Code markup"
         [ "Code" =: "=foo(bar)=" =?> para (code "foo(bar)")