Minetest-WorldEdit/table_save.lua

133 lines
4.2 KiB
Lua
Raw Normal View History

2012-09-20 06:30:20 +02:00
--[[
Save Table to File
Load Table from File
v 1.0
Lua 5.2 compatible
Only Saves Tables, Numbers and Strings
Insides Table References are saved
Does not save Userdata, Metatables, Functions and indices of these
----------------------------------------------------
table.save( table , filename )
on failure: returns an error msg
----------------------------------------------------
table.load( filename or stringtable )
Loads a table that has been saved via the table.save function
on success: returns a previously saved table
on failure: returns as second argument an error msg
----------------------------------------------------
Licensed under the same terms as Lua itself.
]]--
do
-- declare local variables
--// exportstring( string )
--// returns a "Lua" portable version of the string
local function exportstring( s )
return string.format("%q", s)
end
--// The Save Function
function table.save( tbl,filename )
local charS,charE = " ","\n"
local file,err = io.open( filename, "wb" )
if err then return err end
-- initiate variables for save procedure
local tables,lookup = { tbl },{ [tbl] = 1 }
file:write( "return {"..charE )
for idx,t in ipairs( tables ) do
file:write( "-- Table: {"..idx.."}"..charE )
file:write( "{"..charE )
local thandled = {}
for i,v in ipairs( t ) do
thandled[i] = true
local stype = type( v )
-- only handle value
if stype == "table" then
if not lookup[v] then
table.insert( tables, v )
lookup[v] = #tables
end
file:write( charS.."{"..lookup[v].."},"..charE )
elseif stype == "string" then
file:write( charS..exportstring( v )..","..charE )
elseif stype == "number" then
file:write( charS..tostring( v )..","..charE )
end
end
for i,v in pairs( t ) do
-- escape handled values
if (not thandled[i]) then
local str = ""
local stype = type( i )
-- handle index
if stype == "table" then
if not lookup[i] then
table.insert( tables,i )
lookup[i] = #tables
end
str = charS.."[{"..lookup[i].."}]="
elseif stype == "string" then
str = charS.."["..exportstring( i ).."]="
elseif stype == "number" then
str = charS.."["..tostring( i ).."]="
end
if str ~= "" then
stype = type( v )
-- handle value
if stype == "table" then
if not lookup[v] then
table.insert( tables,v )
lookup[v] = #tables
end
file:write( str.."{"..lookup[v].."},"..charE )
elseif stype == "string" then
file:write( str..exportstring( v )..","..charE )
elseif stype == "number" then
file:write( str..tostring( v )..","..charE )
end
end
end
end
file:write( "},"..charE )
end
file:write( "}" )
file:close()
end
--// The Load Function
function table.load( sfile )
local ftables,err = loadfile( sfile )
if err then return _,err end
local tables = ftables()
for idx = 1,#tables do
local tolinki = {}
for i,v in pairs( tables[idx] ) do
if type( v ) == "table" then
tables[idx][i] = tables[v[1]]
end
if type( i ) == "table" and tables[i[1]] then
table.insert( tolinki,{ i,tables[i[1]] } )
end
end
-- link indices
for _,v in ipairs( tolinki ) do
tables[idx][v[2]],tables[idx][v[1]] = tables[idx][v[1]],nil
end
end
return tables[1]
end
-- close do
end
-- ChillCode