Use new flexible metadata type.

* Depend on pandoc 1.12.
* Added yaml dependency.
* `Text.Pandoc.XML`: Removed `stripTags`.  (API change.)
* `Text.Pandoc.Shared`:  Added `metaToJSON`.
  This will be used in writers to create a JSON object for use
  in the templates from the pandoc metadata.
* Revised readers and writers to use the new Meta type.
* `Text.Pandoc.Options`: Added `Ext_yaml_title_block`.
* Markdown reader:  Added support for YAML metadata block.
  Note that it must come at the beginning of the document.
* `Text.Pandoc.Parsing.ParserState`:  Replace `stateTitle`,
  `stateAuthors`, `stateDate` with `stateMeta`.
* RST reader:  Improved metadata.
  Treat initial field list as metadata when standalone specified.
  Previously ALL fields "title", "author", "date" in field lists
  were treated as metadata, even if not at the beginning.
  Use `subtitle` metadata field for subtitle.
* `Text.Pandoc.Templates`:  Export `renderTemplate'` that takes a string
  instead of a compiled template..
* OPML template:  Use 'for' loop for authors.
* Org template: '#+TITLE:' is inserted before the title.
  Previously the writer did this.

1 files changed, 16 insertions, 15 deletions

diff --git a/src/Text/Pandoc/Writers/OPML.hs b/src/Text/Pandoc/Writers/OPML.hs
index f7eb9289a..b71c7cf6e 100644
--- a/src/Text/Pandoc/Writers/OPML.hs
+++ b/src/Text/Pandoc/Writers/OPML.hs
@@ -32,37 +32,38 @@ import Text.Pandoc.Definition
 import Text.Pandoc.XML
 import Text.Pandoc.Shared
 import Text.Pandoc.Options
-import Text.Pandoc.Templates (renderTemplate)
+import Text.Pandoc.Templates (renderTemplate')
 import Text.Pandoc.Writers.HTML (writeHtmlString)
 import Text.Pandoc.Writers.Markdown (writeMarkdown)
-import Data.List ( intercalate )
 import Text.Pandoc.Pretty
 import Data.Time
 import System.Locale (defaultTimeLocale)
+import qualified Text.Pandoc.Builder as B
 
 -- | Convert Pandoc document to string in OPML format.
 writeOPML :: WriterOptions -> Pandoc -> String
-writeOPML opts (Pandoc (Meta tit auths dat) blocks) =
-  let title = writeHtmlInlines tit
-      author = writeHtmlInlines $ intercalate [Space,Str ";",Space] auths
-      date = convertDate dat
-      elements = hierarchicalize blocks
+writeOPML opts (Pandoc meta blocks) =
+  let elements = hierarchicalize blocks
       colwidth = if writerWrapText opts
                     then Just $ writerColumns opts
                     else Nothing
+      meta' = B.setMeta "date" (B.str $ convertDate $ docDate meta) meta
+      Just metadata = metaToJSON
+                      (Just . writeMarkdown def . Pandoc nullMeta)
+                      (Just . trimr . writeMarkdown def . Pandoc nullMeta .
+                         (\ils -> [Plain ils]))
+                      meta'
       main     = render colwidth $ vcat (map (elementToOPML opts) elements)
-      context = writerVariables opts ++
-                [ ("body", main)
-                , ("title", title)
-                , ("date", date)
-                , ("author", author) ]
+      context = setField "body" main
+              $ foldl (\acc (x,y) -> setField x y acc)
+                     metadata (writerVariables opts)
   in  if writerStandalone opts
-         then renderTemplate context $ writerTemplate opts
+         then renderTemplate' (writerTemplate opts) context
          else main
 
 writeHtmlInlines :: [Inline] -> String
 writeHtmlInlines ils = trim $ writeHtmlString def
-                            $ Pandoc (Meta [] [] []) [Plain ils]
+                            $ Pandoc nullMeta [Plain ils]
 
 -- date format: RFC 822: Thu, 14 Jul 2005 23:41:05 GMT
 showDateTimeRFC822 :: UTCTime -> String
@@ -82,7 +83,7 @@ elementToOPML opts (Sec _ _num _ title elements) =
       fromBlk _ = error "fromBlk called on non-block"
       (blocks, rest) = span isBlk elements
       attrs = [("text", writeHtmlInlines title)] ++
-              [("_note", writeMarkdown def (Pandoc (Meta [] [] [])
+              [("_note", writeMarkdown def (Pandoc nullMeta
                               (map fromBlk blocks)))
                 | not (null blocks)]
   in  inTags True "outline" attrs $