how to update cbi variable in luci web interface using lua code before commit?

Question

I'm trying to modify each element in the dynamic list and if those modification went ok and the validation passed, i want to commit the updated variable and not the original. example: i pass "A B C" and "1 2 3 ABC" and i want the function to save them as "ABC" and "123ABC" i'm not having a problem with the validation and deleting spaces (doing the modification) the issue is i don't know how to replace the old strings with the new strings.

i can't post the code but this is a general idea of what i'm doing

list = s:option(DynamicList, "text", "text")
list.parse = function(self, section, novld, ...)
 local listString = luci.http.formvalue(path to the list)
 for key, value in pairs(listString) do
   -- change the value here and delete spaces--
   -- validate the new value --
 end
 Value.parse(self, section, novld, ...)
end

this is the general idea, and i tried to use Value.write(self, section, list) where the list is the same old list but each time i modify a value i update it in the list like this, list[key] = value (after modofication) the thing is, the write function has no effect if the function reached the Value.parse.

Answer 1

this was the solution if anyone may need it.

list.write = function(self, section, value)
local list
if type(value) == "table" then
    list = value
elseif value ~= nil then
    list = { value }
else
    return -- should not happen, .remove() should have been called then
end
for _, item in ipairs(list) do
    list[_] = strip_spaces(item)
end
return Value.write(self, section, list)
end

for more details see this post: link