initial release

cosmic rage/lua/json/decode/array.lua

@@ -0,0 +1,64 @@
+--[[
+	Licensed according to the included 'LICENSE' document
+	Author: Thomas Harning Jr <harningt@gmail.com>
+--]]
+local lpeg = require("lpeg")
+
+local util = require("json.decode.util")
+local jsonutil = require("json.util")
+
+local table_maxn = require("table").maxn
+
+local unpack = unpack
+
+module("json.decode.array")
+
+-- Utility function to help manage slighly sparse arrays
+local function processArray(array)
+	local max_n = table_maxn(array)
+	-- Only populate 'n' if it is necessary
+	if #array ~= max_n then
+		array.n = max_n
+	end
+	if jsonutil.InitArray then
+		array = jsonutil.InitArray(array) or array
+	end
+	return array
+end
+
+local defaultOptions = {
+	trailingComma = true
+}
+
+default = nil -- Let the buildCapture optimization take place
+strict = {
+	trailingComma = false
+}
+
+local function buildCapture(options, global_options)
+	local ignored = global_options.ignored
+	-- arrayItem == element
+	local arrayItem = lpeg.V(util.types.VALUE)
+	local arrayElements = lpeg.Ct(arrayItem * (ignored * lpeg.P(',') * ignored * arrayItem)^0 + 0) / processArray
+
+	options = options and jsonutil.merge({}, defaultOptions, options) or defaultOptions
+	local capture = lpeg.P("[")
+	capture = capture * ignored
+		* arrayElements * ignored
+	if options.trailingComma then
+		capture = capture * (lpeg.P(",") + 0) * ignored
+	end
+	capture = capture * lpeg.P("]")
+	return capture
+end
+
+function register_types()
+	util.register_type("ARRAY")
+end
+
+function load_types(options, global_options, grammar)
+	local capture = buildCapture(options, global_options)
+	local array_id = util.types.ARRAY
+	grammar[array_id] = capture
+	util.append_grammar_item(grammar, "VALUE", lpeg.V(array_id))
+end