--[[ pandoc.lua Copyright © 2017–2019 Albert Krewinkel Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies. THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. ]] --- -- Lua functions for pandoc scripts. -- -- @author Albert Krewinkel -- @copyright © 2017–2019 Albert Krewinkel -- @license MIT local M = {} -- Re-export bundled modules M.List = require 'pandoc.List' M.mediabag = require 'pandoc.mediabag' M.system = require 'pandoc.system' M.types = require 'pandoc.types' M.utils = require 'pandoc.utils' M.text = require 'text' -- Local names for modules which this module depends on. local List = M.List local utils = M.utils ------------------------------------------------------------------------ -- Accessor objects -- -- Create metatables which allow to access numerical indices via accessor -- methods. -- @section -- @local --- Create a new table which allows to access numerical indices via accessor -- functions. -- @local local function create_accessor_behavior (tag) local behavior = {tag = tag} behavior.__eq = utils.equals behavior.__index = function(t, k) if k == "t" then return getmetatable(t)["tag"] end end behavior.__pairs = function (t) return next, t end return behavior end ------------------------------------------------------------------------ -- The base class for types -- @type Type -- @local local Type = {} Type.name = 'Type' Type.__index = Type Type.behavior = { __type = Type, new = function (obj) obj = obj or {} setmetatable(obj, self) return obj end } Type.behavior.__index = Type.behavior --- Set a new behavior for the type, inheriting that of the parent type if none --- is specified explicitly -- @param behavior the behavior object for this type. -- @local function Type:set_behavior (behavior) behavior = behavior or {} behavior.__index = rawget(behavior, '__index') or behavior behavior.__type = self if not getmetatable(behavior) and getmetatable(self) then setmetatable(behavior, getmetatable(self).behavior) end self.behavior = behavior end --- Create a new subtype, using the given table as base. -- @param name name of the new type -- @param[opt] behavior behavioral object for the new type. -- @return a new type -- @local function Type:make_subtype(name, behavior) local newtype = setmetatable({}, self) newtype.name = name newtype.__index = newtype newtype:set_behavior(behavior) return newtype end ------------------------------------------------------------------------ -- The base class for pandoc's AST elements. -- @type AstElement -- @local local AstElement = Type:make_subtype 'AstElement' AstElement.__call = function(t, ...) local success, ret = pcall(t.new, t, ...) if success then return setmetatable(ret, t.behavior) else error(string.format('Constructor for %s failed: %s\n', t.name, ret)) end end --- Make a new subtype which constructs a new value when called. -- @local function AstElement:make_subtype(...) local newtype = Type.make_subtype(self, ...) newtype.__call = self.__call return newtype end --- Create a new constructor -- @local -- @param tag Tag used to identify the constructor -- @param fn Function to be called when constructing a new element -- @param accessors names to use as accessors for numerical fields -- @return function that constructs a new element function AstElement:create_constructor(tag, fn) local constr = self:make_subtype(tag, create_accessor_behavior(tag)) function constr:new(...) return setmetatable(fn(...), self.behavior) end self.constructor = self.constructor or {} self.constructor[tag] = constr return constr end --- Convert AstElement input into a list if necessary. -- @local local function ensureList (x) if x.tag then -- Lists are not tagged, but all elements are return List:new{x} else return List:new(x) end end --- Ensure a given object is an Inline element, or convert it into one. -- @local local function ensureInlineList (x) if type(x) == 'string' then return List:new{M.Str(x)} else return ensureList(x) end end ------------------------------------------------------------------------ -- Meta -- @section Meta --- Create a new Meta object. It sets the metatable of the given table to --- `Meta`. -- @function Meta -- @tparam meta table table containing document meta information M.Meta = AstElement:make_subtype'Meta' M.Meta.behavior.clone = M.types.clone.Meta function M.Meta:new (meta) return meta end ------------------------------------------------------------------------ -- MetaValue -- @section MetaValue M.MetaValue = AstElement:make_subtype('MetaValue') M.MetaValue.behavior.clone = M.types.clone.MetaValue --- Meta blocks -- @function MetaBlocks -- @tparam {Block,...} blocks blocks M.MetaBlocks = M.MetaValue:create_constructor( 'MetaBlocks', function (content) return ensureList(content) end ) --- Meta inlines -- @function MetaInlines -- @tparam {Inline,...} inlines inlines M.MetaInlines = M.MetaValue:create_constructor( 'MetaInlines', function (content) return ensureInlineList(content) end ) --- Meta list -- @function MetaList -- @tparam {MetaValue,...} meta_values list of meta values M.MetaList = M.MetaValue:create_constructor( 'MetaList', function (content) if content.tag == 'MetaList' then return content end return ensureList(content) end ) for k, v in pairs(List) do M.MetaList.behavior[k] = v end --- Meta map -- @function MetaMap -- @tparam table key_value_map a string-indexed map of meta values M.MetaMap = M.MetaValue:create_constructor( "MetaMap", function (mm) return mm end ) --- Creates string to be used in meta data. -- Does nothing, lua strings are meta strings. -- @function MetaString -- @tparam string str string value function M.MetaString(str) return str end --- Creates boolean to be used in meta data. -- Does nothing, lua booleans are meta booleans. -- @function MetaBool -- @tparam boolean bool boolean value function M.MetaBool(bool) return bool end return M