You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
koreader/frontend/dump.lua

76 lines
2.3 KiB
Lua

--[[--
A simple serialization function which won't do uservalues, functions, or loops.
If you need a more full-featured variant, serpent is available in ffi/serpent ;).
]]
local insert = table.insert
local indent_prefix = " "
local function _serialize(what, outt, indent, max_lv, history, pairs_func)
if not max_lv then
max_lv = math.huge
end
if indent > max_lv then
return
end
local datatype = type(what)
if datatype == "table" then
history = history or {}
for up, item in ipairs(history) do
if item == what then
insert(outt, "nil --[[ LOOP:\n")
insert(outt, string.rep(indent_prefix, indent - up))
insert(outt, "^------- ]]")
return
end
end
local new_history = { what, unpack(history) }
local didrun = false
insert(outt, "{")
for k, v in pairs_func(what) do
insert(outt, "\n")
insert(outt, string.rep(indent_prefix, indent+1))
insert(outt, "[")
_serialize(k, outt, indent+1, max_lv, new_history, pairs_func)
insert(outt, "] = ")
_serialize(v, outt, indent+1, max_lv, new_history, pairs_func)
insert(outt, ",")
didrun = true
end
if didrun then
insert(outt, "\n")
insert(outt, string.rep(indent_prefix, indent))
end
insert(outt, "}")
elseif datatype == "string" then
insert(outt, string.format("%q", what))
elseif datatype == "number" then
insert(outt, tostring(what))
elseif datatype == "boolean" then
insert(outt, tostring(what))
elseif datatype == "function" then
insert(outt, tostring(what))
elseif datatype == "nil" then
insert(outt, "nil")
end
end
--[[--Serializes whatever is in `data` to a string that is parseable by Lua.
You can optionally specify a maximum recursion depth in `max_lv`.
@function dump
@param data the object you want serialized (table, string, number, boolean, nil)
@param max_lv optional maximum recursion depth
--]]
local function dump(data, max_lv, ordered)
local out = {}
local pairs_func = ordered and require("ffi/util").orderedPairs or pairs
_serialize(data, out, 0, max_lv, nil, pairs_func)
return table.concat(out)
end
return dump