From 2c66a42ab81d40e771eda0f054c62f22ad45f3d0 Mon Sep 17 00:00:00 2001
From: Albert Krewinkel <albert@zeitkraut.de>
Date: Sat, 23 Dec 2017 13:35:27 +0100
Subject: Lua modules: add function pandoc.utils.normalize_date
The function parses a date and converts it (if possible) to "YYYY-MM-DD"
format.
---
src/Text/Pandoc/Lua/Module/Utils.hs | 12 ++++++++++--
src/Text/Pandoc/Lua/Util.hs | 4 ++++
2 files changed, 14 insertions(+), 2 deletions(-)
(limited to 'src')
diff --git a/src/Text/Pandoc/Lua/Module/Utils.hs b/src/Text/Pandoc/Lua/Module/Utils.hs
index 3c830a4bd..458716a03 100644
--- a/src/Text/Pandoc/Lua/Module/Utils.hs
+++ b/src/Text/Pandoc/Lua/Module/Utils.hs
@@ -33,7 +33,7 @@ import Control.Applicative ((<|>))
import Foreign.Lua (FromLuaStack, Lua, LuaInteger, NumResults)
import Text.Pandoc.Definition (Pandoc, Meta, Block, Inline)
import Text.Pandoc.Lua.StackInstances ()
-import Text.Pandoc.Lua.Util (addFunction)
+import Text.Pandoc.Lua.Util (OrNil (OrNil), addFunction)
import qualified Data.Digest.Pure.SHA as SHA
import qualified Data.ByteString.Lazy as BSL
@@ -44,9 +44,10 @@ import qualified Text.Pandoc.Shared as Shared
pushModule :: Lua NumResults
pushModule = do
Lua.newtable
- addFunction "to_roman_numeral" toRomanNumeral
+ addFunction "normalize_date" normalizeDate
addFunction "sha1" sha1
addFunction "stringify" stringify
+ addFunction "to_roman_numeral" toRomanNumeral
return 1
-- | Calculate the hash of the given contents.
@@ -85,3 +86,10 @@ instance FromLuaStack AstElement where
-- | Convert a number < 4000 to uppercase roman numeral.
toRomanNumeral :: LuaInteger -> Lua String
toRomanNumeral = return . Shared.toRomanNumeral . fromIntegral
+
+-- | Parse a date and convert (if possible) to "YYYY-MM-DD" format. We
+-- limit years to the range 1601-9999 (ISO 8601 accepts greater than
+-- or equal to 1583, but MS Word only accepts dates starting 1601).
+-- Returns nil instead of a string if the conversion failed.
+normalizeDate :: String -> Lua (OrNil String)
+normalizeDate = return . OrNil . Shared.normalizeDate
diff --git a/src/Text/Pandoc/Lua/Util.hs b/src/Text/Pandoc/Lua/Util.hs
index 28d09d339..1f7664fc0 100644
--- a/src/Text/Pandoc/Lua/Util.hs
+++ b/src/Text/Pandoc/Lua/Util.hs
@@ -125,6 +125,10 @@ instance FromLuaStack a => FromLuaStack (OrNil a) where
then return (OrNil Nothing)
else OrNil . Just <$> Lua.peek idx
+instance ToLuaStack a => ToLuaStack (OrNil a) where
+ push (OrNil Nothing) = Lua.pushnil
+ push (OrNil (Just x)) = Lua.push x
+
-- | Helper class for pushing a single value to the stack via a lua function.
-- See @pushViaCall@.
class PushViaCall a where
--
cgit v1.2.3