API change: move writer functions to Text.Pandoc.Writers

Writer helper functions were defined in the top-level Text.Pandoc
module. These functions are moved to the Writer submodule as to enable
reuse in other submodules.

3 files changed, 196 insertions, 154 deletions

diff --git a/pandoc.cabal b/pandoc.cabal
index 8bfd5f653..f9ce1efd2 100644
--- a/pandoc.cabal
+++ b/pandoc.cabal
@@ -382,6 +382,7 @@ Library
                    Text.Pandoc.Readers.Docx,
                    Text.Pandoc.Readers.Odt,
                    Text.Pandoc.Readers.EPUB,
+                   Text.Pandoc.Writers,
                    Text.Pandoc.Writers.Native,
                    Text.Pandoc.Writers.Docbook,
                    Text.Pandoc.Writers.JATS,
diff --git a/src/Text/Pandoc.hs b/src/Text/Pandoc.hs
index afe4bc8c7..345ef3b18 100644
--- a/src/Text/Pandoc.hs
+++ b/src/Text/Pandoc.hs
@@ -70,65 +70,16 @@ module Text.Pandoc
                , setVerbosity
                -- * Error handling
                , module Text.Pandoc.Error
-               -- * Lists of writers
-               , writers
                -- * Readers: converting /to/ Pandoc format
                , module Text.Pandoc.Readers
                -- * Writers: converting /from/ Pandoc format
-               , Writer(..)
-               , writeNative
-               , writeJSON
-               , writeMarkdown
-               , writePlain
-               , writeRST
-               , writeLaTeX
-               , writeBeamer
-               , writeConTeXt
-               , writeTexinfo
-               , writeHtml4
-               , writeHtml4String
-               , writeHtml5
-               , writeHtml5String
-               , writeRevealJs
-               , writeS5
-               , writeSlidy
-               , writeSlideous
-               , writeDZSlides
-               , writeICML
-               , writeDocbook4
-               , writeDocbook5
-               , writeJATS
-               , writeOPML
-               , writeOpenDocument
-               , writeMan
-               , writeMs
-               , writeMediaWiki
-               , writeDokuWiki
-               , writeZimWiki
-               , writeTextile
-               , writeRTF
-               , writeODT
-               , writeDocx
-               , writeEPUB2
-               , writeEPUB3
-               , writeFB2
-               , writeOrg
-               , writeAsciiDoc
-               , writeHaddock
-               , writeCommonMark
-               , writeCustom
-               , writeTEI
-               , writeMuse
+               , module Text.Pandoc.Writers
                -- * Rendering templates and default templates
                , module Text.Pandoc.Templates
                -- * Miscellaneous
-               , getWriter
                , pandocVersion
              ) where
 
-import Data.Aeson
-import qualified Data.ByteString.Lazy as BL
-import Data.List (intercalate)
 import Text.Pandoc.Class
 import Text.Pandoc.Definition
 import Text.Pandoc.Error
@@ -138,107 +89,4 @@ import Text.Pandoc.Options
 import Text.Pandoc.Readers
 import Text.Pandoc.Shared (pandocVersion)
 import Text.Pandoc.Templates
-import qualified Text.Pandoc.UTF8 as UTF8
-import Text.Pandoc.Writers.AsciiDoc
-import Text.Pandoc.Writers.CommonMark
-import Text.Pandoc.Writers.ConTeXt
-import Text.Pandoc.Writers.Custom
-import Text.Pandoc.Writers.Docbook
-import Text.Pandoc.Writers.JATS
-import Text.Pandoc.Writers.Docx
-import Text.Pandoc.Writers.DokuWiki
-import Text.Pandoc.Writers.EPUB
-import Text.Pandoc.Writers.FB2
-import Text.Pandoc.Writers.Haddock
-import Text.Pandoc.Writers.HTML
-import Text.Pandoc.Writers.ICML
-import Text.Pandoc.Writers.LaTeX
-import Text.Pandoc.Writers.Man
-import Text.Pandoc.Writers.Ms
-import Text.Pandoc.Writers.Markdown
-import Text.Pandoc.Writers.MediaWiki
-import Text.Pandoc.Writers.Muse
-import Text.Pandoc.Writers.Native
-import Text.Pandoc.Writers.ODT
-import Text.Pandoc.Writers.OpenDocument
-import Text.Pandoc.Writers.OPML
-import Text.Pandoc.Writers.Org
-import Text.Pandoc.Writers.RST
-import Text.Pandoc.Writers.RTF
-import Text.Pandoc.Writers.TEI
-import Text.Pandoc.Writers.Texinfo
-import Text.Pandoc.Writers.Textile
-import Text.Pandoc.Writers.ZimWiki
-import Text.Parsec.Error
-
-data Writer m = StringWriter (WriterOptions -> Pandoc -> m String)
-              | ByteStringWriter (WriterOptions -> Pandoc -> m BL.ByteString)
-
--- | Association list of formats and writers.
-writers :: PandocMonad m => [ ( String, Writer m) ]
-writers = [
-   ("native"       , StringWriter writeNative)
-  ,("json"         , StringWriter $ \o d -> return $ writeJSON o d)
-  ,("docx"         , ByteStringWriter writeDocx)
-  ,("odt"          , ByteStringWriter writeODT)
-  ,("epub"         , ByteStringWriter writeEPUB3)
-  ,("epub2"        , ByteStringWriter writeEPUB2)
-  ,("epub3"        , ByteStringWriter writeEPUB3)
-  ,("fb2"          , StringWriter writeFB2)
-  ,("html"         , StringWriter writeHtml5String)
-  ,("html4"        , StringWriter writeHtml4String)
-  ,("html5"        , StringWriter writeHtml5String)
-  ,("icml"         , StringWriter writeICML)
-  ,("s5"           , StringWriter writeS5)
-  ,("slidy"        , StringWriter writeSlidy)
-  ,("slideous"     , StringWriter writeSlideous)
-  ,("dzslides"     , StringWriter writeDZSlides)
-  ,("revealjs"     , StringWriter writeRevealJs)
-  ,("docbook"      , StringWriter writeDocbook5)
-  ,("docbook4"     , StringWriter writeDocbook4)
-  ,("docbook5"     , StringWriter writeDocbook5)
-  ,("jats"         , StringWriter writeJATS)
-  ,("opml"         , StringWriter writeOPML)
-  ,("opendocument" , StringWriter writeOpenDocument)
-  ,("latex"        , StringWriter writeLaTeX)
-  ,("beamer"       , StringWriter writeBeamer)
-  ,("context"      , StringWriter writeConTeXt)
-  ,("texinfo"      , StringWriter writeTexinfo)
-  ,("man"          , StringWriter writeMan)
-  ,("ms"           , StringWriter writeMs)
-  ,("markdown"     , StringWriter writeMarkdown)
-  ,("markdown_strict" , StringWriter writeMarkdown)
-  ,("markdown_phpextra" , StringWriter writeMarkdown)
-  ,("markdown_github" , StringWriter writeMarkdown)
-  ,("markdown_mmd" , StringWriter writeMarkdown)
-  ,("plain"        , StringWriter writePlain)
-  ,("rst"          , StringWriter writeRST)
-  ,("mediawiki"    , StringWriter writeMediaWiki)
-  ,("dokuwiki"     , StringWriter writeDokuWiki)
-  ,("zimwiki"      , StringWriter writeZimWiki)
-  ,("textile"      , StringWriter writeTextile)
-  ,("rtf"          , StringWriter writeRTF)
-  ,("org"          , StringWriter writeOrg)
-  ,("asciidoc"     , StringWriter writeAsciiDoc)
-  ,("haddock"      , StringWriter writeHaddock)
-  ,("commonmark"   , StringWriter writeCommonMark)
-  ,("tei"          , StringWriter writeTEI)
-  ,("muse"         , StringWriter writeMuse)
-  ]
-
-getWriter :: PandocMonad m => String -> Either String (Writer m)
-getWriter s
-  = case parseFormatSpec s of
-         Left e  -> Left $ intercalate "\n" [m | Message m <- errorMessages e]
-         Right (writerName, setExts) ->
-             case lookup writerName writers of
-                     Nothing -> Left $ "Unknown writer: " ++ writerName
-                     Just (StringWriter r) -> Right $ StringWriter $
-                             \o -> r o{ writerExtensions = setExts $
-                                              getDefaultExtensions writerName }
-                     Just (ByteStringWriter r) -> Right $ ByteStringWriter $
-                             \o -> r o{ writerExtensions = setExts $
-                                              getDefaultExtensions writerName }
-
-writeJSON :: WriterOptions -> Pandoc -> String
-writeJSON _ = UTF8.toStringLazy . encode
+import Text.Pandoc.Writers
diff --git a/src/Text/Pandoc/Writers.hs b/src/Text/Pandoc/Writers.hs
new file mode 100644
index 000000000..0181f41c9
--- /dev/null
+++ b/src/Text/Pandoc/Writers.hs
@@ -0,0 +1,193 @@
+{-
+Copyright (C) 2006-2016 John MacFarlane <jgm@berkeley.edu>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+-}
+{-# LANGUAGE FlexibleInstances   #-}
+{-# LANGUAGE GADTs               #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+
+{- |
+   Module      : Text.Pandoc
+   Copyright   : Copyright (C) 2006-2016 John MacFarlane
+   License     : GNU GPL, version 2 or above
+
+   Maintainer  : John MacFarlane <jgm@berkeley.edu>
+   Stability   : alpha
+   Portability : portable
+
+This helper module exports all writers functions.
+-}
+module Text.Pandoc.Writers
+  (
+    -- * Writers: converting /from/ Pandoc format
+      Writer(..)
+    , writers
+    , writeAsciiDoc
+    , writeBeamer
+    , writeCommonMark
+    , writeConTeXt
+    , writeCustom
+    , writeDZSlides
+    , writeDocbook4
+    , writeDocbook5
+    , writeDocx
+    , writeDokuWiki
+    , writeEPUB2
+    , writeEPUB3
+    , writeFB2
+    , writeHaddock
+    , writeHtml4
+    , writeHtml4String
+    , writeHtml5
+    , writeHtml5String
+    , writeICML
+    , writeJATS
+    , writeJSON
+    , writeLaTeX
+    , writeMan
+    , writeMarkdown
+    , writeMediaWiki
+    , writeMs
+    , writeMuse
+    , writeNative
+    , writeODT
+    , writeOPML
+    , writeOpenDocument
+    , writeOrg
+    , writePlain
+    , writeRST
+    , writeRTF
+    , writeRevealJs
+    , writeS5
+    , writeSlideous
+    , writeSlidy
+    , writeTEI
+    , writeTexinfo
+    , writeTextile
+    , writeZimWiki
+    , getWriter
+    ) where
+
+import Data.Aeson
+import Data.List (intercalate)
+import Text.Pandoc.Class
+import Text.Pandoc.Definition
+import Text.Pandoc.Options
+import Text.Pandoc.Writers.AsciiDoc
+import Text.Pandoc.Writers.CommonMark
+import Text.Pandoc.Writers.ConTeXt
+import Text.Pandoc.Writers.Custom
+import Text.Pandoc.Writers.Docbook
+import Text.Pandoc.Writers.Docx
+import Text.Pandoc.Writers.DokuWiki
+import Text.Pandoc.Writers.EPUB
+import Text.Pandoc.Writers.FB2
+import Text.Pandoc.Writers.HTML
+import Text.Pandoc.Writers.Haddock
+import Text.Pandoc.Writers.ICML
+import Text.Pandoc.Writers.JATS
+import Text.Pandoc.Writers.LaTeX
+import Text.Pandoc.Writers.Man
+import Text.Pandoc.Writers.Markdown
+import Text.Pandoc.Writers.MediaWiki
+import Text.Pandoc.Writers.Ms
+import Text.Pandoc.Writers.Muse
+import Text.Pandoc.Writers.Native
+import Text.Pandoc.Writers.ODT
+import Text.Pandoc.Writers.OPML
+import Text.Pandoc.Writers.OpenDocument
+import Text.Pandoc.Writers.Org
+import Text.Pandoc.Writers.RST
+import Text.Pandoc.Writers.RTF
+import Text.Pandoc.Writers.TEI
+import Text.Pandoc.Writers.Texinfo
+import Text.Pandoc.Writers.Textile
+import Text.Pandoc.Writers.ZimWiki
+import Text.Parsec.Error
+import qualified Text.Pandoc.UTF8 as UTF8
+import qualified Data.ByteString.Lazy as BL
+
+data Writer m = StringWriter (WriterOptions -> Pandoc -> m String)
+              | ByteStringWriter (WriterOptions -> Pandoc -> m BL.ByteString)
+
+-- | Association list of formats and writers.
+writers :: PandocMonad m => [ ( String, Writer m) ]
+writers = [
+   ("native"       , StringWriter writeNative)
+  ,("json"         , StringWriter $ \o d -> return $ writeJSON o d)
+  ,("docx"         , ByteStringWriter writeDocx)
+  ,("odt"          , ByteStringWriter writeODT)
+  ,("epub"         , ByteStringWriter writeEPUB3)
+  ,("epub2"        , ByteStringWriter writeEPUB2)
+  ,("epub3"        , ByteStringWriter writeEPUB3)
+  ,("fb2"          , StringWriter writeFB2)
+  ,("html"         , StringWriter writeHtml5String)
+  ,("html4"        , StringWriter writeHtml4String)
+  ,("html5"        , StringWriter writeHtml5String)
+  ,("icml"         , StringWriter writeICML)
+  ,("s5"           , StringWriter writeS5)
+  ,("slidy"        , StringWriter writeSlidy)
+  ,("slideous"     , StringWriter writeSlideous)
+  ,("dzslides"     , StringWriter writeDZSlides)
+  ,("revealjs"     , StringWriter writeRevealJs)
+  ,("docbook"      , StringWriter writeDocbook5)
+  ,("docbook4"     , StringWriter writeDocbook4)
+  ,("docbook5"     , StringWriter writeDocbook5)
+  ,("jats"         , StringWriter writeJATS)
+  ,("opml"         , StringWriter writeOPML)
+  ,("opendocument" , StringWriter writeOpenDocument)
+  ,("latex"        , StringWriter writeLaTeX)
+  ,("beamer"       , StringWriter writeBeamer)
+  ,("context"      , StringWriter writeConTeXt)
+  ,("texinfo"      , StringWriter writeTexinfo)
+  ,("man"          , StringWriter writeMan)
+  ,("ms"           , StringWriter writeMs)
+  ,("markdown"     , StringWriter writeMarkdown)
+  ,("markdown_strict" , StringWriter writeMarkdown)
+  ,("markdown_phpextra" , StringWriter writeMarkdown)
+  ,("markdown_github" , StringWriter writeMarkdown)
+  ,("markdown_mmd" , StringWriter writeMarkdown)
+  ,("plain"        , StringWriter writePlain)
+  ,("rst"          , StringWriter writeRST)
+  ,("mediawiki"    , StringWriter writeMediaWiki)
+  ,("dokuwiki"     , StringWriter writeDokuWiki)
+  ,("zimwiki"      , StringWriter writeZimWiki)
+  ,("textile"      , StringWriter writeTextile)
+  ,("rtf"          , StringWriter writeRTF)
+  ,("org"          , StringWriter writeOrg)
+  ,("asciidoc"     , StringWriter writeAsciiDoc)
+  ,("haddock"      , StringWriter writeHaddock)
+  ,("commonmark"   , StringWriter writeCommonMark)
+  ,("tei"          , StringWriter writeTEI)
+  ,("muse"         , StringWriter writeMuse)
+  ]
+
+getWriter :: PandocMonad m => String -> Either String (Writer m)
+getWriter s
+  = case parseFormatSpec s of
+         Left e  -> Left $ intercalate "\n" [m | Message m <- errorMessages e]
+         Right (writerName, setExts) ->
+             case lookup writerName writers of
+                     Nothing -> Left $ "Unknown writer: " ++ writerName
+                     Just (StringWriter r) -> Right $ StringWriter $
+                             \o -> r o{ writerExtensions = setExts $
+                                              getDefaultExtensions writerName }
+                     Just (ByteStringWriter r) -> Right $ ByteStringWriter $
+                             \o -> r o{ writerExtensions = setExts $
+                                              getDefaultExtensions writerName }
+
+writeJSON :: WriterOptions -> Pandoc -> String
+writeJSON _ = UTF8.toStringLazy . encode