From 9b750f7d879b1da386e49ecfd51ef9d023dc5d66 Mon Sep 17 00:00:00 2001
From: Albert Krewinkel <albert@zeitkraut.de>
Date: Tue, 3 Oct 2017 13:13:45 +0200
Subject: [PATCH 1/2] Lua.PandocModule: promote addFunction to top level
This reduces some boilerplate.
---
data/pandoc.lua | 2 +-
src/Text/Pandoc/Lua/PandocModule.hs | 24 ++++++++++--------------
2 files changed, 11 insertions(+), 15 deletions(-)
diff --git a/data/pandoc.lua b/data/pandoc.lua
index bce4e9326..e6cfbc90c 100644
--- a/data/pandoc.lua
+++ b/data/pandoc.lua
@@ -782,7 +782,7 @@ M.UpperAlpha = "UpperAlpha"
-- assert(block.content[1].t == "Emph")
function M.read(markup, format)
format = format or "markdown"
- local pd = pandoc.__read(format, markup)
+ local pd = pandoc._read(format, markup)
if type(pd) == "string" then
error(pd)
else
diff --git a/src/Text/Pandoc/Lua/PandocModule.hs b/src/Text/Pandoc/Lua/PandocModule.hs
index 6a84a4350..c689edc4e 100644
--- a/src/Text/Pandoc/Lua/PandocModule.hs
+++ b/src/Text/Pandoc/Lua/PandocModule.hs
@@ -41,6 +41,7 @@ import Data.IORef
import Data.Maybe (fromMaybe)
import Data.Text (pack)
import Foreign.Lua (Lua, FromLuaStack, ToLuaStack, NumResults, liftIO)
+import Foreign.Lua.FunctionCalling (ToHaskellFunction)
import Text.Pandoc.Class (readDataFile, runIO,
runIOorExplode, setUserDataDir, CommonState(..),
putCommonState, fetchItem, setMediaBag)
@@ -62,15 +63,9 @@ pushPandocModule datadir = do
script <- liftIO (pandocModuleScript datadir)
status <- Lua.loadstring script
unless (status /= Lua.OK) $ Lua.call 0 1
- Lua.push "__read"
- Lua.pushHaskellFunction readDoc
- Lua.rawset (-3)
- Lua.push "sha1"
- Lua.pushHaskellFunction sha1HashFn
- Lua.rawset (-3)
- Lua.push "pipe"
- Lua.pushHaskellFunction pipeFn
- Lua.rawset (-3)
+ addFunction "pipe" pipeFn
+ addFunction "_read" readDoc
+ addFunction "sha1" sha1HashFn
-- | Get the string representation of the pandoc module
pandocModuleScript :: Maybe FilePath -> IO String
@@ -102,11 +97,12 @@ pushMediaBagModule commonState mediaBagRef = do
addFunction "list" (mediaDirectoryFn mediaBagRef)
addFunction "fetch" (fetch commonState mediaBagRef)
return ()
- where
- addFunction name fn = do
- Lua.push name
- Lua.pushHaskellFunction fn
- Lua.rawset (-3)
+
+addFunction :: ToHaskellFunction a => String -> a -> Lua ()
+addFunction name fn = do
+ Lua.push name
+ Lua.pushHaskellFunction fn
+ Lua.rawset (-3)
sha1HashFn :: BL.ByteString
-> Lua NumResults
From 371f9b708478700992a74864985cfea0af2fd4c3 Mon Sep 17 00:00:00 2001
From: Albert Krewinkel <albert@zeitkraut.de>
Date: Tue, 3 Oct 2017 20:45:11 +0200
Subject: [PATCH 2/2] pandoc.lua: use wrapper funciton for pipe command
The pipe command is wrapped in a lua function, throwing a lua error if
the command returns with an error. A wrapper is needed as Haskell
functions exposed to lua may not throw lua errors due to limitations of
hslua.
The error handling is written such that a table can be returned as an
error object in the future. This is potentially useful when finer
control is required while catching the error in lua code. Current
limitations of hslua require error objects to be strings.
---
data/pandoc.lua | 23 +++++++++++++++++++++++
src/Text/Pandoc/Lua/PandocModule.hs | 2 +-
2 files changed, 24 insertions(+), 1 deletion(-)
diff --git a/data/pandoc.lua b/data/pandoc.lua
index e6cfbc90c..fc83103e0 100644
--- a/data/pandoc.lua
+++ b/data/pandoc.lua
@@ -790,6 +790,29 @@ function M.read(markup, format)
end
end
+--- Runs command with arguments, passing it some input, and returns the output.
+-- @treturn string Output of command.
+-- @usage
+-- local ec, output = pandoc.pipe("sed", {"-e","s/a/b/"}, "abc")
+function M.pipe (command, args, input)
+ local ec, output = pandoc._pipe(command, args, input)
+ if ec ~= 0 then
+ err = setmetatable(
+ { command = command, error_code = ec, output = output},
+ { __tostring = function(e)
+ return "Error running " .. e.command
+ .. " (error code " .. e.error_code .. "): "
+ .. e.output
+ end
+ }
+ )
+ -- TODO: drop the wrapping call to `tostring` as soon as hslua supports
+ -- non-string error objects.
+ error(tostring(err))
+ end
+ return output
+end
+
--- Use functions defined in the global namespace to create a pandoc filter.
-- All globally defined functions which have names of pandoc elements are
-- collected into a new table.
diff --git a/src/Text/Pandoc/Lua/PandocModule.hs b/src/Text/Pandoc/Lua/PandocModule.hs
index c689edc4e..f9b072dff 100644
--- a/src/Text/Pandoc/Lua/PandocModule.hs
+++ b/src/Text/Pandoc/Lua/PandocModule.hs
@@ -63,7 +63,7 @@ pushPandocModule datadir = do
script <- liftIO (pandocModuleScript datadir)
status <- Lua.loadstring script
unless (status /= Lua.OK) $ Lua.call 0 1
- addFunction "pipe" pipeFn
+ addFunction "_pipe" pipeFn
addFunction "_read" readDoc
addFunction "sha1" sha1HashFn