Re: how to read lua table present in file

[Sean Conner <sean@...>]

It was thus said that the Great prashantkumar dhotre once stated:
> hi
> i am new to lua. i have a query related to table reading from file.
> i have a config file in lua table format:
> example:
> return {
>     ["param1"] = {
>         ["attribute"] = {
>             ["myparam"] = 1,
>         }
>    },
>    ["param2"] = 1
> }
> 
> could you please let me know how do i read this file and access my config
> file parameters ?
> Thanks

For Lua 5.1 (you did not mention which version you are using), I use:

	CONF =
	{
	  getenv = getenv, -- we allow this function be be called in the conf file
	  -- put any other functions you deem "safe" to call from a config 
	  -- file here as well ... 
	}
	  
	local configfile,err = loadfile("myconfigfile.conf")
	if not configfile then
	  os.exit(1) -- or handle a missing config file
	end
	  
	setfenv(configfile,CONF)
	configfile()
	print(CONF['param1']['attribute']['myparam'])

For Lua 5.2 and above, it changes slightly:

	CONF =
	{
	  getenv = getenv,
	}
	  
	local configfile,err = loadfile("myconfigfile.conf","t",CONF)
	if not configfile then
	  os.exit(1) -- or handle a missing config file
	end
	
	configfile()	
	print(CONF['param1']['attribute']['myparam'])

I allow some functions (like getenv()) to be called from a config file
because it's nice to allow something like:

	basedir = getenv("HOME") .. "/datadir"
	webdir  = getenv("HOME") .. "/public_html"
	
in a config file, but hey, leave the CONF table empty if you want maximum
security.

  -spc