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			794 lines
		
	
	
	
		
			29 KiB
		
	
	
	
		
			Lua
		
	
	
	
	
	
			
		
		
	
	
			794 lines
		
	
	
	
		
			29 KiB
		
	
	
	
		
			Lua
		
	
	
	
	
	
| --- anselme main module
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| 
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| --- Anselme Lua API reference
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| --
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| -- We actively support LuaJIT and Lua 5.4. Lua 5.1, 5.2 and 5.3 *should* work but I don't always test against them.
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| --
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| -- This documentation is generated from the main module file `anselme.lua` using `ldoc --ext md anselme.lua`.
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| --
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| -- Example usage:
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| -- ```lua
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| -- local anselme = require("anselme") -- load main module
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| --
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| -- local vm = anselme() -- create new VM
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| -- vm:loadgame("game") -- load some scripts, etc.
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| -- local interpreter = vm:rungame() -- create a new interpreter using what was loaded with :loadgame
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| --
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| -- -- simple function to convert text event data into a string
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| -- -- in your game you may want to handle tags, here we ignore them for simplicity
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| -- local function format_text(text)
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| --   local r = ""
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| --   for _, l in ipairs(t) do
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| --     r = r .. l.text
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| --   end
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| --   return r
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| -- end
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| --
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| -- -- event loop
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| -- repeat
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| --   local event, data = interpreter:step() -- progress script until next event
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| --   if event == "text" then
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| --     print(format_text(d))
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| --   elseif event == "choice" then
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| --     for j, choice in ipairs(d) do
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| --       print(j.."> "..format_text(choice))
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| --     end
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| --     interpreter:choose(io.read())
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| --   elseif event == "error" then
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| --     error(data)
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| --   end
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| -- until t == "return" or t == "error"
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| -- ```
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| --
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| -- Calling the Anselme main module will create a return a new [VM](#vms).
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| --
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| -- The main module also contain a few fields:
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| --
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| -- @type anselme
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| local anselme = {
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| 	--- Anselme version information table.
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| 	--
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| 	-- Contains version informations as number (higher means more recent) of Anselme divied in a few categories:
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| 	--
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| 	-- * `save`, which is incremented at each update which may break save compatibility
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| 	-- * `language`, which is incremented at each update which may break script file compatibility
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| 	-- * `api`, which is incremented at each update which may break Lua API compatibility
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| 	versions = {
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| 		save = 1,
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| 		language = 22,
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| 		api = 5
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| 	},
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| 	--- General version number.
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| 	--
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| 	-- It is incremented at each update.
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| 	version = 23,
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| 	--- Currently running [interpreter](#interpreters).
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| 	-- `nil` if no interpreter running.
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| 	running = nil
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| }
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| package.loaded[...] = anselme
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| 
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| -- load libs
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| local anselme_root = (...):gsub("anselme$", "")
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| local preparse = require(anselme_root.."parser.preparser")
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| local postparse = require(anselme_root.."parser.postparser")
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| local expression = require(anselme_root.."parser.expression")
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| local eval = require(anselme_root.."interpreter.expression")
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| local injections = require(anselme_root.."parser.common").injections
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| local run_line = require(anselme_root.."interpreter.interpreter").run_line
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| local run = require(anselme_root.."interpreter.interpreter").run
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| local to_lua = require(anselme_root.."interpreter.common").to_lua
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| local merge_state = require(anselme_root.."interpreter.common").merge_state
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| local stdfuncs = require(anselme_root.."stdlib.functions")
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| local bootscript = require(anselme_root.."stdlib.bootscript")
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| local copy = require(anselme_root.."common").copy
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| local should_keep_variable = require(anselme_root.."interpreter.common").should_keep_variable
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| 
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| -- wrappers for love.filesystem / luafilesystem
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| local function list_directory(path)
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| 	local t = {}
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| 	if love then
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| 		t = love.filesystem.getDirectoryItems(path)
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| 	else
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| 		local lfs = require("lfs")
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| 		for item in lfs.dir(path) do
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| 			table.insert(t, item)
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| 		end
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| 	end
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| 	return t
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| end
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| local function is_directory(path)
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| 	if love then
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| 		return not not love.filesystem.getInfo(path, "directory")
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| 	else
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| 		local lfs = require("lfs")
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| 		return lfs.attributes(path, "mode") == "directory"
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| 	end
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| end
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| local function is_file(path)
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| 	if love then
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| 		return not not love.filesystem.getInfo(path, "file")
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| 	else
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| 		local lfs = require("lfs")
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| 		return lfs.attributes(path, "mode") == "file"
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| 	end
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| end
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| 
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| --- Interpreters
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| --
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| -- An interpreter is in charge of running Anselme code and is spawned from a [VM](#vms).
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| -- Several interpreters from the same VM can run at the same time.
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| --
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| -- Typically, you would have a interpreter for each script that need at the same time, for example one for every NPC
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| -- that is currently talking.
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| --
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| -- Each interpreter can only run one script at a time, and will run it sequentially.
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| -- You can advance in the script by calling the `:step` method, which will run the script until an event is sent (for example some text needs to be displayed),
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| -- which will pause the whole interpreter until `:step` is called again.
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| --
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| -- @type interpreter
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| local interpreter_methods = {
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| 	--- interpreter state
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| 	-- for internal use, you shouldn't touch this
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| 	-- @local
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| 	state = nil,
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| 	--- [VM](#vms) this interpreter belongs to.
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| 	vm = nil,
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| 	--- String, type of the event that stopped the interpreter (`nil` if interpreter is still running).
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| 	end_event = nil,
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| 
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| 	--- Run the interpreter until the next event.
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| 	-- Returns event type (string), data (any).
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| 	--
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| 	-- Will merge changed variables on successful script end.
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| 	--
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| 	-- If event is `"return"` or `"error"`, the interpreter can not be stepped further and should be discarded.
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| 	--
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| 	-- Default event types and their associated data:
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| 	-- * `text`: text to display, data is a list of text elements, each with a `text` field, containing the text contents, and a `tags` field, containing the tags associated with this text
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| 	-- * `choice`: choices to choose from, data is a list of choices Each of these choice is a list of text elements like for the `text` event
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| 	-- * `return`: when the script ends, data is the returned value (`nil` if nothing returned)
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| 	-- * `error`: when there is an error, data is the error message.
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| 	--
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| 	-- See [LANGUAGE.md](LANGUAGE.md) for more details on events.
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| 	step = function(self)
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| 		-- check status
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| 		if self.end_event then
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| 			return "error", ("interpreter can't be restarted after receiving a %s event"):format(self.end_event)
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| 		end
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| 		if coroutine.status(self.state.interpreter.coroutine) ~= "suspended" then
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| 			return "error", ("can't step interpreter because it has already finished or is already running (coroutine status: %s)"):format(coroutine.status(self.state.interpreter.coroutine))
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| 		end
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| 		-- handle interrupt
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| 		if self.state.interpreter.interrupt then
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| 			local expr = self.state.interpreter.interrupt
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| 			if expr == true then
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| 				return "return", "" -- nothing to do after interrupt
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| 			else
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| 				local line = self.state.interpreter.running_line
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| 				local namespace = self:current_namespace()
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| 				-- replace state with interrupted state
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| 				local exp, err = expression(expr, self.state.interpreter.global_state, namespace or "")
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| 				if not exp then return "error", ("%s; during interrupt %q at %s"):format(err, expr, line and line.source or "unknown") end
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| 				local r, e = self.vm:run(exp)
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| 				if not r then return "error", e end
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| 				self.state = r.state
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| 			end
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| 		end
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| 		-- run
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| 		local previous = anselme.running
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| 		anselme.running = self
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| 		local success, event, data = coroutine.resume(self.state.interpreter.coroutine)
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| 		anselme.running = previous
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| 		if not success then event, data = "error", event end
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| 		if event == "return" then merge_state(self.state) end
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| 		if event == "return" or event == "error" then self.end_event = event end
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| 		return event, data
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| 	end,
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| 
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| 	--- Select a choice.
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| 	-- `i` is the index (number) of the choice in the choice list (from the choice event's data).
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| 	--
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| 	-- The choice will be selected on the next interpreter step.
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| 	--
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| 	-- Returns this interpreter.
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| 	choose = function(self, i)
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| 		self.state.interpreter.choice_selected = tonumber(i)
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| 		return self
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| 	end,
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| 
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| 	--- Interrupt (abort the currently running script) the interpreter on the next step, executing an expression (string, if specified) in the current namespace instead.
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| 	--
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| 	-- Returns this interpreter.
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| 	interrupt = function(self, expr)
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| 		self.state.interpreter.interrupt = expr or true
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| 		return self
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| 	end,
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| 
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| 	--- Returns the namespace (string) the last ran line belongs to.
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| 	current_namespace = function(self)
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| 		local line = self.state.interpreter.running_line
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| 		local namespace = ""
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| 		if line then
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| 			local cur_line = line
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| 			namespace = cur_line.namespace
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| 			while not namespace do
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| 				local block = cur_line.parent_block
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| 				if not block.parent_line then break end -- reached root
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| 				cur_line = block.parent_line
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| 				namespace = cur_line.namespace
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| 			end
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| 		end
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| 		return namespace
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| 	end,
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| 
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| 	--- Run an expression (string) or block, optionally in a specific namespace (string, will use root namespace if not specified).
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| 	-- This may trigger events and must be called from within the interpreter coroutine (i.e. from a function called from a running script).
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| 	--
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| 	-- No automatic merge if this change the interpreter state, merge is done once we reach end of script in a call to `:step` as usual.
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| 	--
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| 	-- Returns the returned value (nil if nothing returned).
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| 	run = function(self, expr, namespace)
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| 		-- check status
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| 		if coroutine.status(self.state.interpreter.coroutine) ~= "running" then
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| 			error("run must be called from whithin the interpreter coroutine")
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| 		end
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| 		-- parse
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| 		local err
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| 		if type(expr) ~= "table" then expr, err = expression(tostring(expr), self.state.interpreter.global_state, namespace or "") end
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| 		if not expr then coroutine.yield("error", err) end
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| 		-- run
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| 		local r, e
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| 		if expr.type == "block" then
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| 			r, e = run(self.state, expr)
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| 		else
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| 			r, e = eval(self.state, expr)
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| 		end
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| 		if not r then coroutine.yield("error", e) end
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| 		if self.state.interpreter.current_event then -- flush final events
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| 			local rf, re = run_line(self.state, { type = "flush_events" })
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| 			if re then coroutine.yield("error", re) end
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| 			if rf then r = rf end
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| 		end
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| 		return to_lua(r)
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| 	end,
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| 	--- Evaluate an expression (string) or block, optionally in a specific namespace (string, will use root namespace if not specified).
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| 	-- The expression can't yield events.
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| 	-- Can be called from outside the interpreter coroutine. Will create a new coroutine that operate on this interpreter state.
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| 	--
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| 	-- No automatic merge if this change the interpreter state, merge is done once we reach end of script in a call to `:step` as usual.
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| 	--
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| 	-- Returns the returned value in case of success (nil if nothing returned).
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| 	--
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| 	-- Returns nil, error message in case of error.
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| 	eval = function(self, expr, namespace)
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| 		if self.end_event then
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| 			return "error", ("interpreter can't be restarted after receiving a %s event"):format(self.end_event)
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| 		end
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| 		-- parse
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| 		local err
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| 		if type(expr) ~= "table" then expr, err = expression(tostring(expr), self.state.interpreter.global_state, namespace or "") end
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| 		if not expr then return nil, err end
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| 		-- run
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| 		local co = coroutine.create(function()
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| 			local r, e
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| 			if expr.type == "block" then
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| 				r, e = run(self.state, expr)
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| 			else
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| 				r, e = eval(self.state, expr)
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| 			end
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| 			if not r then return "error", e end
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| 			return "return", r
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| 		end)
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| 		local previous = anselme.running
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| 		anselme.running = self
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| 		local success, event, data = coroutine.resume(co)
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| 		anselme.running = previous
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| 		if not success then
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| 			return nil, event
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| 		elseif event == "error" then
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| 			self.end_event = "error"
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| 			return nil, data
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| 		elseif event ~= "return" then
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| 			return nil, ("evaluated expression generated an %q event; at %s"):format(event, self.state.interpreter.running_line.source)
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| 		else
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| 			return to_lua(data)
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| 		end
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| 	end,
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| }
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| interpreter_methods.__index = interpreter_methods
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| 
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| --- VMs
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| --
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| -- A VM stores the state required to run Anselme scripts. Each VM is completely independant from each other.
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| --
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| -- @type vm
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| local vm_mt = {
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| 	--- anselme state
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| 	-- for internal use, you shouldn't touch this
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| 	-- @local
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| 	state = nil,
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| 
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| 	--- loaded game state
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| 	-- for internal use, you shouldn't touch this
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| 	-- @local
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| 	game = nil,
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| 
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| 	--- Wrapper for loading a whole set of scripts (a "game").
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| 	-- Should be preferred to other loading functions if possible as this sets all the common options on its own.
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| 	--
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| 	-- Requires LÖVE or LuaFileSystem.
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| 	--
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| 	-- Will load from the directory given by `path` (string), in order:
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| 	-- * `config.ans`, which will be executed in the "config" namespace and may contains various optional configuration options:
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| 	--   * `anselme version`: number, version of the anselme language this game was made for
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| 	--   * `game version`: any, version information of the game. Can be used to perform eventual migration of save with an old version in the main file.
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| 	--                        Always included in saved variables.
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| 	--   * `language`: string, built-in language file to load
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| 	--   * `inject directory`: string, directory that may contain "function start.ans", "checkpoint end.ans", etc. which content will be used to setup
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| 	--                       the custom code injection methods (see vm:setinjection)
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| 	--   * `global directory`: string, path of global script directory. Every script file and subdirectory in the path will be loaded in the global namespace.
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| 	--   * `start expression`: string, expression that will be ran when starting the game
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| 	-- * files in the global directory, if defined in config.ans
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| 	-- * every other file in the path and subdirectories, using their path as namespace (i.e., contents of path/world1/john.ans will be defined in a function world1.john)
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| 	--
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| 	-- Returns this VM in case of success.
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| 	--
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| 	-- Returns nil, error message in case of error.
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| 	loadgame = function(self, path)
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| 		if self.game then error("game already loaded") end
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| 		-- load config
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| 		if is_file(path.."/config.ans") then
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| 			local s, e = self:loadfile(path.."/config.ans", "config")
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| 			if not s then return s, e end
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| 			s, e = self:eval("config")
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| 			if e then return s, e end
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| 		end
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| 		-- get config
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| 		self.game = {
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| 			anselme_version = self:eval("config.anselme version"),
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| 			game_version = self:eval("config.game version"),
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| 			language = self:eval("config.language"),
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| 			inject_directory = self:eval("config.inject directory"),
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| 			global_directory = self:eval("config.global directory"),
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| 			start_expression = self:eval("config.start expression")
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| 		}
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| 		-- check language version
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| 		if self.game.anselme_version and self.game.anselme_version ~= anselme.versions.language then
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| 			return nil, ("trying to load game made for Anselme language %s, but currently using version %s"):format(self.game.anselme_version, anselme.versions.language)
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| 		end
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| 		-- load language
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| 		if self.game.language then
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| 			local s, e = self:loadlanguage(self.game.language)
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| 			if not s then return s, e end
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| 		end
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| 		-- load injections
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| 		if self.game.inject_directory then
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| 			for inject, ninject in pairs(injections) do
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| 				local f = io.open(path.."/"..self.game.inject_directory.."/"..inject..".ans", "r")
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| 				if f then
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| 					self.state.inject[ninject] = f:read("*a")
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| 					f:close()
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| 				end
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| 			end
 | |
| 		end
 | |
| 		-- load global scripts
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| 		for _, item in ipairs(list_directory(path.."/"..self.game.global_directory)) do
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| 			if item:match("[^%.]") then
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| 				local p = path.."/"..self.game.global_directory.."/"..item
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| 				local s, e
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| 				if is_directory(p) then
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| 					s, e = self:loaddirectory(p)
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| 				elseif item:match("%.ans$") then
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| 					s, e = self:loadfile(p)
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| 				end
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| 				if not s then return s, e end
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| 			end
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| 		end
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| 		-- load other files
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| 		for _, item in ipairs(list_directory(path)) do
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| 			if item:match("[^%.]") and
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| 				item ~= "config.ans" and
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| 				item ~= self.game.global_directory and
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| 				item ~= self.game.inject_directory
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| 			then
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| 				local p = path.."/"..item
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| 				local s, e
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| 				if is_directory(p) then
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| 					s, e = self:loaddirectory(p, item)
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| 				elseif item:match("%.ans$") then
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| 					s, e = self:loadfile(p, item:gsub("%.ans$", ""))
 | |
| 				end
 | |
| 				if not s then return s, e end
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| 			end
 | |
| 		end
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| 		return self
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| 	end,
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| 	--- Return a interpreter which runs the game start expression (if given).
 | |
| 	--
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| 	-- Returns interpreter in case of success.
 | |
| 	--
 | |
| 	-- Returns nil, error message in case of error.
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| 	rungame = function(self)
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| 		if not self.game then error("no game loaded") end
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| 		if self.game.start_expression then
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| 			return self:run(self.game.start_expression)
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| 		else
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| 			return self:run("()")
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| 		end
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| 	end,
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| 
 | |
| 	--- Load code from a string.
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| 	-- Similar to Lua's code loading functions.
 | |
| 	--
 | |
| 	-- Compared to their Lua equivalents, these also take an optional `name` argument (default="") that set the namespace to load the code in. Will define a new function is specified; otherwise, code will be parsed but not executable from an expression (as it is not named).
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| 	--
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| 	-- Returns parsed block in case of success.
 | |
| 	--
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| 	-- Returns nil, error message in case of error.
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| 	loadstring = function(self, str, name, source)
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| 		local s, e = preparse(self.state, str, name or "", source)
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| 		if not s then return s, e end
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| 		return s
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| 	end,
 | |
| 	--- Load code from a file.
 | |
| 	-- See `vm:loadstring`.
 | |
| 	loadfile = function(self, path, name)
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| 		local content
 | |
| 		if love then
 | |
| 			local e
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| 			content, e = love.filesystem.read(path)
 | |
| 			if not content then return content, e end
 | |
| 		else
 | |
| 			local f, e = io.open(path, "r")
 | |
| 			if not f then return f, e end
 | |
| 			content = f:read("*a")
 | |
| 			f:close()
 | |
| 		end
 | |
| 		local s, err = self:loadstring(content, name, path)
 | |
| 		if not s then return s, err end
 | |
| 		return s
 | |
| 	end,
 | |
| 	-- Load every file in a directory, using filename (without .ans extension) as its namespace.
 | |
| 	--
 | |
| 	-- Requires LÖVE or LuaFileSystem.
 | |
| 	--
 | |
| 	-- Returns this VM in case of success.
 | |
| 	--
 | |
| 	-- Returns nil, error message in case of error.
 | |
| 	loaddirectory = function(self, path, name)
 | |
| 		if not name then name = "" end
 | |
| 		name = name == "" and "" or name.."."
 | |
| 		for _, item in ipairs(list_directory(path)) do
 | |
| 			if item:match("[^%.]") then
 | |
| 				local p = path.."/"..item
 | |
| 				local s, e
 | |
| 				if is_directory(p) then
 | |
| 					s, e = self:loaddirectory(p, name..item)
 | |
| 				elseif item:match("%.ans$") then
 | |
| 					s, e = self:loadfile(p, name..item:gsub("%.ans$", ""))
 | |
| 				end
 | |
| 				if not s then return s, e end
 | |
| 			end
 | |
| 		end
 | |
| 		return self
 | |
| 	end,
 | |
| 
 | |
| 	--- Set aliases for built-in variables 👁️, 🔖 and 🏁 that will be defined on every new checkpoint and function.
 | |
| 	-- This does not affect variables that were defined before this function was called.
 | |
| 	-- Set to nil for no alias.
 | |
| 	--
 | |
| 	-- Returns this VM.
 | |
| 	setaliases = function(self, seen, checkpoint, reached)
 | |
| 		self.state.builtin_aliases["👁️"] = seen
 | |
| 		self.state.builtin_aliases["🔖"] = checkpoint
 | |
| 		self.state.builtin_aliases["🏁"] = reached
 | |
| 		return self
 | |
| 	end,
 | |
| 	--- Set some code that will be injected at specific places in all code loaded after this is called.
 | |
| 	-- Can typically be used to define variables for every function like 👁️, setting some value on every function resume, etc.
 | |
| 	--
 | |
| 	-- Possible inject types:
 | |
| 	-- * `"function start"`: injected at the start of every non-scoped function
 | |
| 	-- * `"function end"`: injected at the end of every non-scoped function
 | |
| 	-- * `"function return"`: injected at the end of each return's children that is contained in a non-scoped function
 | |
| 	-- * `"checkpoint start"`: injected at the start of every checkpoint
 | |
| 	-- * `"checkpoint end"`: injected at the end of every checkpoint
 | |
| 	-- * `"scoped function start"`: injected at the start of every scoped function
 | |
| 	-- * `"scoped function end"`: injected at the end of every scoped function
 | |
| 	-- * `"scoped function return"`: injected at the end of each return's children that is contained in a scoped function
 | |
| 	--
 | |
| 	-- Set `code` to nil to disable the inject.
 | |
| 	--
 | |
| 	-- Returns this VM.
 | |
| 	setinjection = function(self, inject, code)
 | |
| 		assert(injections[inject], ("unknown injection type %q"):format(inject))
 | |
| 		self.state.inject[injections[inject]] = code
 | |
| 		return self
 | |
| 	end,
 | |
| 
 | |
| 	--- Load and execute a built-in language file.
 | |
| 	--
 | |
| 	-- The language file may optionally contain the special variables:
 | |
| 	--   * alias 👁️: string, default alias for 👁️
 | |
| 	--   * alias 🏁: string, default alias for 🏁
 | |
| 	--   * alias 🔖: string, default alias for 🔖
 | |
| 	--
 | |
| 	-- Returns this VM in case of success.
 | |
| 	--
 | |
| 	-- Returns nil, error message in case of error.
 | |
| 	loadlanguage = function(self, lang)
 | |
| 		local namespace = "anselme.languages."..lang
 | |
| 		-- execute language file
 | |
| 		local code = require(anselme_root.."stdlib.languages."..lang)
 | |
| 		local s, e = self:loadstring(code, namespace, lang)
 | |
| 		if not s then return s, e end
 | |
| 		s, e = self:eval(namespace)
 | |
| 		if e then return s, e end
 | |
| 		-- set aliases for built-in variables
 | |
| 		local seen_alias = self:eval(namespace..".alias 👁️")
 | |
| 		local checkpoint_alias = self:eval(namespace..".alias 🔖")
 | |
| 		local reached_alias = self:eval(namespace..".alias 🏁")
 | |
| 		self:setaliases(seen_alias, checkpoint_alias, reached_alias)
 | |
| 		return self
 | |
| 	end,
 | |
| 
 | |
| 	--- Define functions from Lua.
 | |
| 	--
 | |
| 	-- * `signature`: string, full signature of the function
 | |
| 	-- * `fn`: function (Lua function or table, see examples in `stdlib/functions.lua`)
 | |
| 	--
 | |
| 	-- Returns this VM.
 | |
| 	loadfunction = function(self, signature, fn)
 | |
| 		if type(signature) == "table" then
 | |
| 			for k, v in pairs(signature) do
 | |
| 				local s, e = self:loadfunction(k, v)
 | |
| 				if not s then return nil, e end
 | |
| 			end
 | |
| 		else
 | |
| 			if type(fn) == "function" then fn = { value = fn } end
 | |
| 			self.state.link_next_function_definition_to_lua_function = fn
 | |
| 			local s, e = self:loadstring("$"..signature, "", "lua")
 | |
| 			if not s then return nil, e end
 | |
| 			assert(self.state.link_next_function_definition_to_lua_function == nil, "unexpected error while defining lua function")
 | |
| 			return self
 | |
| 		end
 | |
| 		return self
 | |
| 	end,
 | |
| 
 | |
| 	--- Save/load script state
 | |
| 	--
 | |
| 	-- Only saves variables full names and values, so make sure to not change important variables, checkpoints and functions names between a save and a load.
 | |
| 	-- Also only save variables with usable identifiers, so will skip functions with arguments, operators, etc. (i.e. every scoped functions).
 | |
| 	-- Loading should be done after loading all the game scripts (otherwise you will "variable already defined" errors).
 | |
| 	--
 | |
| 	-- Returns this VM.
 | |
| 	load = function(self, data)
 | |
| 		assert(anselme.versions.save == data.anselme.versions.save, ("trying to load data from an incompatible version of Anselme; save was done using save version %s but current version is %s"):format(data.anselme.versions.save, anselme.versions.save))
 | |
| 		for k, v in pairs(data.variables) do
 | |
| 			self.state.variables[k] = v
 | |
| 		end
 | |
| 		return self
 | |
| 	end,
 | |
| 	--- Save script state.
 | |
| 	-- See `vm:load`.
 | |
| 	--
 | |
| 	-- Returns save data.
 | |
| 	save = function(self)
 | |
| 		local vars = {}
 | |
| 		for k, v in pairs(self.state.variables) do
 | |
| 			if should_keep_variable(self.state, k, v) then
 | |
| 				if v.type == "object" then -- filter object attributes
 | |
| 					local attributes = {}
 | |
| 					for kk, vv in pairs(v.value.attributes) do
 | |
| 						if should_keep_variable(self.state, kk, vv) then
 | |
| 							attributes[kk] = vv
 | |
| 						end
 | |
| 					end
 | |
| 					vars[k] = {
 | |
| 						type = "object",
 | |
| 						value = {
 | |
| 							class = v.value.class,
 | |
| 							attributes = attributes
 | |
| 						}
 | |
| 					}
 | |
| 				else
 | |
| 					vars[k] = v
 | |
| 				end
 | |
| 			end
 | |
| 		end
 | |
| 		return {
 | |
| 			anselme = {
 | |
| 				versions = anselme.versions,
 | |
| 				version = anselme.version
 | |
| 			},
 | |
| 			variables = vars
 | |
| 		}
 | |
| 	end,
 | |
| 
 | |
| 	--- Perform parsing that needs to be done after loading code.
 | |
| 	-- This is automatically ran before starting an interpreter, but you may want to execute it before if you want to check for parsing error manually.
 | |
| 	--
 | |
| 	-- Returns self in case of success.
 | |
| 	--
 | |
| 	-- Returns nil, error message in case of error
 | |
| 	postload = function(self)
 | |
| 		if #self.state.queued_lines > 0 then
 | |
| 			local r, e = postparse(self.state)
 | |
| 			if not r then return r, e end
 | |
| 		end
 | |
| 		return self
 | |
| 	end,
 | |
| 
 | |
| 	--- Enable feature flags.
 | |
| 	-- Available flags:
 | |
| 	-- * `"strip trailing spaces"`: remove trailing spaces from choice and text events (enabled by default)
 | |
| 	-- * `"strip duplicate spaces"`: remove duplicated spaces between text elements from choice and text events (enabled by default)
 | |
| 	--
 | |
| 	-- Returns this VM.
 | |
| 	enable = function(self, ...)
 | |
| 		for _, flag in ipairs{...} do
 | |
| 			self.state.feature_flags[flag] = true
 | |
| 		end
 | |
| 		return self
 | |
| 	end,
 | |
| 	--- Disable features flags.
 | |
| 	-- Returns this VM.
 | |
| 	disable = function(self, ...)
 | |
| 		for _, flag in ipairs{...} do
 | |
| 			self.state.feature_flags[flag] = nil
 | |
| 		end
 | |
| 		return self
 | |
| 	end,
 | |
| 
 | |
| 	--- Run code.
 | |
| 	-- Will merge state after successful execution
 | |
| 	--
 | |
| 	-- * `expr`: expression to evaluate (string or parsed expression), or a block to run
 | |
| 	-- * `namespace`(default=""): namespace to evaluate the expression in
 | |
| 	-- * `tags`(default={}): defaults tags when evaluating the expression (Lua value)
 | |
| 	--
 | |
| 	-- Return interpreter in case of success.
 | |
| 	--
 | |
| 	-- Returns nil, error message in case of error.
 | |
| 	run = function(self, expr, namespace, tags)
 | |
| 		local s, e = self:postload()
 | |
| 		if not s then return s, e end
 | |
| 		--
 | |
| 		local err
 | |
| 		if type(expr) ~= "table" then expr, err = expression(tostring(expr), self.state, namespace or "") end
 | |
| 		if not expr then return expr, err end
 | |
| 		-- interpreter state
 | |
| 		local interpreter
 | |
| 		interpreter = {
 | |
| 			state = {
 | |
| 				inject = self.state.inject,
 | |
| 				feature_flags = self.state.feature_flags,
 | |
| 				builtin_aliases = self.state.builtin_aliases,
 | |
| 				aliases = setmetatable({}, { __index = self.state.aliases }),
 | |
| 				functions = self.state.functions, -- no need for a cache as we can't define or modify any function from the interpreter for now
 | |
| 				variable_constraints = self.state.variable_constraints, -- no cache as constraints are expected to be constant
 | |
| 				variable_constants = self.state.variable_constants,
 | |
| 				variables = setmetatable({}, {
 | |
| 					__index = function(variables, k)
 | |
| 						local cache = getmetatable(variables).cache
 | |
| 						if cache[k] == nil then
 | |
| 							cache[k] = copy(self.state.variables[k], getmetatable(variables).copy_cache)
 | |
| 						end
 | |
| 						return cache[k]
 | |
| 					end,
 | |
| 					-- variables that keep current state and should be cleared at each checkpoint
 | |
| 					cache = {}, -- cache of previously read values (copies), to get repeatable reads & handle mutable types without changing global state
 | |
| 					modified_tables = {}, -- list of modified tables (copies) that should be merged with global state on next checkpoint
 | |
| 					copy_cache = {}, -- table of [original table] = copied table. Automatically filled by copy().
 | |
| 					-- keep track of scoped variables in scoped functions [fn line] = {{scoped variables}, next scope, ...}
 | |
| 					-- (scoped variables aren't merged on checkpoint, shouldn't be cleared at checkpoints)
 | |
| 					-- (only stores scoped variables that have been reassigned at some point (i.e. every accessed one since they start as undefined))
 | |
| 					scoped = {}
 | |
| 				}),
 | |
| 				interpreter = {
 | |
| 					-- constant
 | |
| 					global_state = self.state,
 | |
| 					coroutine = coroutine.create(function() return "return", interpreter:run(expr, namespace) end),
 | |
| 					-- status
 | |
| 					running_line = nil,
 | |
| 					-- choice event
 | |
| 					choice_selected = nil,
 | |
| 					-- skip next choices until next event change (to skip currently running choice block when resuming from a checkpoint)
 | |
| 					skip_choices_until_flush = nil,
 | |
| 					-- active event buffer stack
 | |
| 					event_buffer_stack = {},
 | |
| 					-- current event waiting to be sent
 | |
| 					current_event = nil,
 | |
| 					-- interrupt
 | |
| 					interrupt = nil,
 | |
| 					-- tag stack
 | |
| 					tags = {},
 | |
| 					-- default tags for everything in this interpreter (Lua values)
 | |
| 					base_lua_tags = tags,
 | |
| 				},
 | |
| 			},
 | |
| 			vm = self
 | |
| 		}
 | |
| 		return setmetatable(interpreter, interpreter_methods)
 | |
| 	end,
 | |
| 	--- Evaluate code.
 | |
| 	-- Behave like `:run`, except the expression can not emit events and will return the result of the expression directly.
 | |
| 	-- Merge state after sucessful execution automatically like `:run`.
 | |
| 	--
 | |
| 	-- * `expr`: expression to evaluate (string or parsed expression), or a block to evaluate
 | |
| 	-- * `namespace`(default=""): namespace to evaluate the expression in
 | |
| 	-- * `tags`(default={}): defaults tags when evaluating the expression (Lua value)
 | |
| 	--
 | |
| 	-- Return value in case of success (nil if nothing returned).
 | |
| 	--
 | |
| 	-- Returns nil, error message in case of error.
 | |
| 	eval = function(self, expr, namespace, tags)
 | |
| 		local interpreter, err = self:run("()", namespace, tags)
 | |
| 		if not interpreter then return interpreter, err end
 | |
| 		local r, e = interpreter:eval(expr, namespace)
 | |
| 		if e then return r, e end
 | |
| 		assert(interpreter:step() == "return") -- trigger merge / end-of-script things
 | |
| 		return r
 | |
| 	end
 | |
| }
 | |
| vm_mt.__index = vm_mt
 | |
| 
 | |
| -- return anselme module
 | |
| return setmetatable(anselme, {
 | |
| 	__call = function()
 | |
| 		-- global state
 | |
| 		local state = {
 | |
| 			inject = {
 | |
| 				-- function_start = "code block...", ...
 | |
| 			},
 | |
| 			feature_flags = {
 | |
| 				["strip trailing spaces"] = true,
 | |
| 				["strip duplicate spaces"] = true
 | |
| 			},
 | |
| 			builtin_aliases = {
 | |
| 				-- ["👁️"] = "seen",
 | |
| 				-- ["🔖"] = "checkpoint",
 | |
| 				-- ["🏁"] = "reached"
 | |
| 			},
 | |
| 			aliases = {
 | |
| 				-- ["bonjour.salutation"] = "hello.greeting", ...
 | |
| 			},
 | |
| 			functions = {
 | |
| 				-- ["script.fn"] = {
 | |
| 				-- 	{
 | |
| 				-- 		function or checkpoint table
 | |
| 				-- 	}, ...
 | |
| 				-- }, ...
 | |
| 			},
 | |
| 			variable_constraints = {
 | |
| 				-- foo = { constraint }, ...
 | |
| 			},
 | |
| 			variable_constants = {
 | |
| 				-- foo = true, ...
 | |
| 			},
 | |
| 			variables = {
 | |
| 				-- foo = {
 | |
| 				-- 	type = "number",
 | |
| 				-- 	value = 42
 | |
| 				-- }, ...
 | |
| 			},
 | |
| 			queued_lines = {
 | |
| 				-- { line = line, namespace = "foo" }, ...
 | |
| 			},
 | |
| 			link_next_function_definition_to_lua_function = nil -- temporarly set to tell the preparser to link a anselme function definition with a lua function
 | |
| 		}
 | |
| 		local vm = setmetatable({ state = state }, vm_mt)
 | |
| 		-- bootscript
 | |
| 		local boot = assert(vm:loadstring(bootscript, "", "boot script"))
 | |
| 		local _, e = vm:eval(boot)
 | |
| 		if e then error(e) end
 | |
| 		-- lua-defined functions
 | |
| 		assert(vm:loadfunction(stdfuncs.lua))
 | |
| 		-- anselme-defined functions
 | |
| 		local ansfunc = assert(vm:loadstring(stdfuncs.anselme, "", "built-in functions"))
 | |
| 		_, e = vm:eval(ansfunc)
 | |
| 		if e then return error(e) end
 | |
| 		return vm
 | |
| 	end
 | |
| })
 |