Proposal: Lua Table Notation + load change

[Julien Duminil <julien.duminil@...>]

Hi List,

Here is my two-in-one proposal :

* PROPOSAL 1: Create a JSON-like Lua-compatible format (we can call it LTN for Lua Table Notation or LuT for LuaTable or whatever you want).

This format must be:
- A subset of the Lua grammar (the Lua-compatible part), so that we don’t need another parser to read those data in a Lua enabled software.
- Easy to read in another language (the JSON-like part), so that it could be a JSON replacement for data interchange.
- Bonus: Supported by the official Lua website, to give more visibility to either this data format and Lua.

* PROPOSAL 2: Change the behavior of dofile, load, loadfile, etc. so that if the source only contains a table, the returned chunk returns this table.

Some examples here:
- example 1:
	local position = load(“{ x = 5, y = 10 }”)()
- example 2:
	-- my_light_module.lua:
	{
		var = “some value”,
		log = function(self, …) print("log: ", ...) end
	}
	-- now you can do: local my_mod = require ’my_light_module’
	-- note that this example has very limited use cases, because log can't access var
- example 3:
    local data = dofile 'my_data.lut' -- here is the link between the two proposals :)

Maybe this behavior could also be extended to return the value if the source contains only a boolean, a string or a number.

* Here is a LTN grammar proposal example:

	tableconstructor ::= ‘{’ [fieldlist] ‘}’

	key ::=  false | true | Number | String

	value ::=  key | tableconstructor | nil

	fieldlist ::= field {fieldsep field} [fieldsep]

	field ::= ‘[’ key ‘]’ ‘=’ value | Name ‘=’ value | value

	fieldsep ::= ‘,’ | ‘;’

Maybe tableconstructor should be allowed in key to tease non-Lua users, but it can complicate the internal storage when parsed in some other languages ...
And in a such format, Number, String and Name must be defined more precisely.

What do you think about this proposal?

Julien

PS: I like the way the JSON grammar is displayed on http://www.json.org/