lua open a file with a table and change certain values - lua

Question

I have a file with a large table. Need to open it, get certain values and replace other values with the new ones. With this example, Females and Males Classroom a and b must equal Teachers Classroom a and b.
Read as much as I can on IO, but I cannot seem to get this to work correctly. Any help will be greatly appreciated.
--file with sample data to test, original file has 7000+lines
theData =
{
["theSchool"] =
{
["theTeachers"] =
{
["theClassroom"] =
{
["a"] = 001,
["b"] = 002,
},
},
["theFemales"] =
{
["theClassroom"] =
{
["a"] = 005,
["b"] = 010,
},
},
["theMales"] =
{
["theClassroom"] =
{
["a"] = 012,
["b"] = 014,
},
},
},
}
Then the function file looks like this
local file = io.open(filepath,'r')
local newCa = '["a"] = '..theData.theSchool.theTeachers.theClassroom.a
local newCb = '["b"] = '..theData.theSchool.theTeachers.theClassroom.b
local replaceFa = '["a"] = '..tostring(theData.theSchool.theFemales.theClassroom.a)
local replaceFb = '["b"] = '..tostring(theData.theSchool.theFemales.theClassroom.b)
local replaceMa = '["a"] = '..tostring(theData.theSchool.theMales.theClassroom.a)
local replaceMb = '["b"] = '..tostring(theData.theSchool.theMales.theClassroom.b)
file:close()
--Will it work?
print("Original Values:")
print(newCa)
print(newCb)
print(replaceFa)
print(replaceFb)
print(replaceMa)
print(replaceMb)
file = io.open(filepath,'r+')
function lines_from(filepath)
lines = {}
for line in io.lines(filepath) do
lines[#lines + 1] = line
end
return lines
end
local lines = lines_from(filepath)
for k,v in ipairs(lines) do
if v == replaceFa then
file:write(newCa..'\n')
elseif v == replaceFb then
file:write(newCb..'\n')
elseif v == replaceMa then
file:write(newCa..'\n')
elseif v == replaceMb then
file:write(newCb..'\n')
else
file:write(v..'\n')
end
--('[' .. k .. ']', v)
end
--replaceF = {[a] = newCa, [b] = newCb}
--replaceM = {[a] = newCa, [b] = newCb}
--file:write(replaceF)
--file:write(replaceM)
--print(tostring(theData.theSchool.theFemales.theClassroom.a))
file:close()
file = io.open(filepath,'r')
--Did it work?
print("New Values:")
print(theData.theSchool.theTeachers.theClassroom.a)
print(theData.theSchool.theTeachers.theClassroom.b)
print(theData.theSchool.theFemales.theClassroom.a)
print(theData.theSchool.theFemales.theClassroom.b)
print(theData.theSchool.theMales.theClassroom.a)
print(theData.theSchool.theMales.theClassroom.b)```
> I'll remove all the print things after it works.

Answer 1

try this solution, loading the table in one read of the file will be faster, and writing is also better with one command write
--- read
local handle = io.open("data.lua",'rb')
local data = handle:read("*a")
handle:close()
data = data .. "\n return theData"
local t = loadstring(data)()
-- edit
theData.theSchool.theTeachers.theClassroom.a = theData.theSchool.theTeachers.theClassroom.a + 1
-- write
local function concat(t, r)
r = r or {}
for k,v in pairs(t) do
if type(v)=="table" then
r[#r+1] = string.format('\t["%s"]={\n',k )
concat(v, r)
r[#r+1] = "\t},\n"
else
r[#r+1] = string.format('\t\t["%s"]=%03s,\n',k ,v )
end
end
return r
end
local r = concat(t)
local text = "theData = { \n " .. table.concat(r) .. "}"
print(text) -- just control
local handle = io.open("data.lua",'wb')
local data = handle:write(text)
handle:close()