Removed she-bang line.

README.rst

@@ -22,7 +22,7 @@ try `pandoc-zotxt <https://github.com/egh/zotxt>`_,
 which works with Pandoc 1.12 or later (but also requires Python_ 2.7).
 
 1. Download the `current release
-   <https://codeload.github.com/odkr/pandoc-zotxt/tar.gz/v0.2.2>`_.
+   <https://codeload.github.com/odkr/pandoc-zotxt/tar.gz/v0.2.3>`_.
 2. Unpack it.
 3. Copy the whole directory to the ``filters``
    subdirectory of your Pandoc data directory.
@@ -39,9 +39,9 @@ If you are using a Unix-ish operating system, you can do all of the above by::
         sed -n 's/^Default user data directory: //p')
     mkdir -p "${PANDOC_DATA_DIR:?}/filters"
     cd "${PANDOC_DATA_DIR:?}/filters"
-    curl https://codeload.github.com/odkr/pandoc-zotxt.lua/tar.gz/v0.2.2 |
+    curl https://codeload.github.com/odkr/pandoc-zotxt.lua/tar.gz/v0.2.3 |
         tar -xz
-    sudo cp pandoc-zotxt.lua-0.2.2/man/pandoc-zotxt.lua.1 \
+    sudo cp pandoc-zotxt.lua-0.2.3/man/pandoc-zotxt.lua.1 \
         /usr/local/share/man/man1
 
 

pandoc-zotxt.lua

@@ -1,7 +1,6 @@
-#!/usr/local/bin/lua
 --- pandoc-zotxt.lua Looks up citations in Zotero and adds references. 
 --
--- @release 0.2.2
+-- @release 0.2.3
 -- @author Odin Kroeger
 -- @copyright 2018 Odin Kroeger
 --
@@ -38,11 +37,23 @@ local ZOTXT_KEYTYPES = {'easykey', 'betterbibtexkey', 'key'}
 -- Boilerplate
 -- ===========
 
+local pairs = pairs
+local ipairs = ipairs
+local tostring = tostring
+local type = type
+
 local package = package
+local string = string
+local math = math
+local floor = math.floor
+local concat = table.concat
+local insert = table.insert
+local remove = table.remove
+
 local text = require 'text'
 
 do
-    local s_dir = string.match(PANDOC_SCRIPT_FILE, '(.-)[\\/][^\\/]-$') or '.'
+    local s_dir = PANDOC_SCRIPT_FILE:match('(.-)[\\/][^\\/]-$') or '.'
     local path_sep = package.config:sub(1, 1)
     local lua_vers = {}
     for _, v in ipairs({_VERSION:sub(5, 7), '5.3'}) do lua_vers[v] = true end
@@ -70,30 +81,34 @@ end
 do
     local keytypes = ZOTXT_KEYTYPES
     local fetch = pandoc.mediabag.fetch
+    local concat = concat
+    local insert = insert
+    local remove = remove
 
     ---  Gets bibliographic data from Zotero.
     --
     -- Tries to get bibliographic data by citation key, trying different
-    -- types of citation keys, starting with the last keytype using which
+    -- types of citation keys, starting with the last type for which
     -- a lookup was successful.
     --
     -- The constant ``ZOTXT_QUERY_URL`` defines where to get data from.
     -- The constant ``ZOTXT_KEYTYPES`` defines what keytypes to try.
     -- See <https://github.com/egh/zotxt> for details.
     --
+    -- @tparam string key The lookup key.
+    --
     -- @return If the cited source was found, bibliographic data for
-    --         that source as CSL JSON string.
-    -- @return Otherwise, nil and the error message of the lookup
-    --         attempt for the first keytype.
-    function get_source_json (citekey)
+    --  that source as CSL JSON string. Otherwise, nil and the error 
+    --  message of the lookup attempt for the first keytype.
+    function get_source_json (key)
         local _, reply
         for i = 1, #keytypes do
-            local query_url = ZOTXT_QUERY_URL .. keytypes[i] .. '=' .. citekey
+            local query_url = concat({ZOTXT_QUERY_URL, keytypes[i], '=', key})
             _, reply = fetch(query_url, '.')
             if reply:sub(1, 1) == '[' then
                 if i > 1 then
-                    local keytype = table.remove(keytypes, i)
-                    table.insert(keytypes, 1, keytype)
+                    local keytype = remove(keytypes, i)
+                    insert(keytypes, 1, keytype)
                 end
                 return reply
             end
@@ -112,14 +127,14 @@ end
 -- @parem data Data of any type.
 --
 -- @return The given data, with all numbers converted into strings.
-function stringify_values (data)
+function stringify (data)
     local data_type = type(data)
     if data_type == 'table' then
         local s = {}
-        for k, v in pairs(data) do s[k] = stringify_values(v) end
+        for k, v in pairs(data) do s[k] = stringify(v) end
         return s
     elseif data_type == 'number' then
-        return tostring(math.floor(data))
+        return tostring(floor(data))
     else
         return data
     end
@@ -128,29 +143,34 @@ end
 
 --- Retrieves bibliographic data for sources from Zotero.
 -- 
--- @param citekeys A list of citation keys.
+-- @tparam {string,...} keys A list of keys.
 --
--- @return The cited sources,
---         as a list of CSL compliant multi-dimensional tables.
+-- @treturn {table,...} The cited sources, in CSL data format.
 --
 -- Prints error messages to STDERR if a source cannot be found.
 function get_sources (citekeys)
+    local decode = json.decode
+    local insert = insert
+    local get_source_json = get_source_json
+    local stringify = stringify
     local sources = {}
     for _, citekey in ipairs(citekeys) do
         local data, err = get_source_json(citekey)
         if data == nil then
             io.stderr:write('pandoc-zotxt.lua: ' .. err .. '\n')
         else
-            local source = stringify_values(json.decode(data)[1])
+            local source = stringify(decode(data)[1])
             source.id = citekey
-            table.insert(sources, source)
+            insert(sources, source)
         end
     end
     return sources
 end
 
 
 do
+    local insert = insert
+    local ipairs = ipairs
     local citekeys = {}
     local seen = {}
 
@@ -161,11 +181,12 @@ do
     --
     -- @param citations A pandoc.Cite element.
     function collect_sources (citations)
-        for _, citation in ipairs(citations.citations) do
-            id = citation.id
+        local c = citations.citations
+        for i = 1, #c do
+            id = c[i].id
             if seen[id] == nil then
                 seen[id] = true
-                table.insert(citekeys, id)
+                insert(citekeys, id)
             end
         end
     end