Add the "set width" command

This is mostly needed for embedding, since there doesn't seem to be
any practical (let alone portable) standard way to notify pancake of
emacs window size changes.

In pancake.el, width adjustment is now getting done automatically
whenever any other command gets issued.

1 files changed, 4 insertions, 2 deletions

diff --git a/Pancake.hs b/Pancake.hs
index 129585d..5d49b1a 100644
--- a/Pancake.hs
+++ b/Pancake.hs
@@ -74,6 +74,7 @@ data LoopState = LS { history :: Sliding (URI, P.Pandoc)
                     , embedded :: Bool
                     , interrupted :: Bool
                     , unclutterRegexps :: [(Regex, String)]
+                    , columns :: Maybe Int
                     }
 
 -- | Renders a parsed document.
@@ -81,7 +82,7 @@ printDoc :: MonadIO m => URI -> P.Pandoc -> StateT LoopState m ()
 printDoc uri doc = do
   term <- liftIO setupTermFromEnv
   st <- get
-  let cols = fromMaybe 80 $ getCapability term termColumns
+  let cols = fromMaybe 80 $ columns st <|> getCapability term termColumns
       l = renderDoc cols (conf st) doc
       textLines = rLines l
   modify (\s -> s { rendered = l })
@@ -315,6 +316,7 @@ command Quit = liftIO $ do
   when exists $ removeDirectoryRecursive dir
 command Interrupt =
   putErrLn "Received SIGINT. Interrupt twice in a row to quit."
+command (SetWidth w) = modify $ \s -> s { columns = w }
 
 -- | Reads commands, runs them.
 eventLoop :: MonadIO m => StateT LoopState m ()
@@ -353,7 +355,7 @@ main = do
   tid <- myThreadId
   _ <- installHandler sigINT (Catch (throwTo tid UserInterrupt)) Nothing
   let run e = runStateT (updateConfig >> eventLoop)
-              (LS ([],[]) 0 [] def e False [])
+              (LS ([],[]) 0 [] def e False [] Nothing)
               >> pure ()
   case getOpt Permute options args of
     ([], [], []) -> run False