I don't quite understand what ipairs does. Help?

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#1

Hello, I’m currently a developer that’s learning a lot of new things such as OOP and some other stuff, but recently I have heard about ipairs on Roblox, I’ve watched a lot of stuff about it but still don’t quite understand it, May anyone explain it to me? Thank you -MattVSNNL

#2
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#3

So it’s basically like GetOrderedDataStores where it ascends or descends from highest or lowest? In ipairs case only descends

#4

Nothing to do with OO.
In Lua you have the data structure table, a table has keys and values. Keys could be either a number or a string. If the numbers are consistent and start with the lowest index possible (in Lua 1) - the table is acting like the data structure array.
ipairs allows you to loop through that array. If you have keys that are not consistent nor numbers - it will not loop through them. For that we use pairs.
Personally, I don’t use ipairs at all lol

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#6

As @rotbotrotbot explained, tables have two structures: dictionaries and arrays.
Any table that is not an array behaves as a dictionary. For a table to be an array it must start with index 1 and not have any missing value in between indeces, and must be consistent keys (only numbers)

Ipairs will follow the array rule, in order, until a value is nil, that’s why you shouldn’t use ipairs for any other thing than arrays.

You can imagine ipairs as this:

local tab = {}
for i = 1, #tab, 1 do
      local val = tab[i]
      if val == nil then
      break
      end
end

Whereas pairs will go through every item in the table, but not in order

I generally never use ipairs because of what I mentioned, it stops, if you generally need ordering just use a for i loop

#7
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