First, solve the problem of finding an item in a table (we will say where it is in particular):
1 | function find(tab, element) |
2 | for index, value in pairs(tab) do |
3 | if value == element then |
find will return nil if element wasn't in tab, otherwise it will return where in tab it is, ie, tab[find(tab, element)] == element.
Thus to check if something is in a table:
1 | if find(tab, "foo") then |
We could just string a few together to see if they have multiple things:
1 | if find(tab, "foo") and find(tab, "bar") then |
It's also straightforward to use a loop to check if all of the things are in the table:
1 | local required = {"foo", "bar"} |
3 | for _, thing in pairs(required) do |
4 | haveAll = haveAll and find(tab, thing) |
The limitation of this solution is that we can't require more than one a thing.
1 | if find(tab, "foo") and find(tab, "foo") then |
3 | if find(tab, "foo") then |
Thus we could make a "count" (or find multiple) function:
1 | function findAll(tab, element) |
3 | for index, value in pairs(tab) do |
4 | if value == element then |
5 | table.insert(where, index) |
Now findAll will return an empty list if it isn't in tab, otherwise it will return a list of elements.
Thus
1 | if #findAll(tab, "foo") >= 1 then |
And we can require 2 foo and 3 bar like this:
1 | if #findAll(tab, "foo") >= 2 and findAll(tab, "bar") >= 3 then |
To put this into a loop, we can make a bunch of pairings:
1 | local required = { {"foo", 2}, {"bar", 3} } |
3 | for _, thing in pairs(required) do |
6 | haveAll = haveAll and ( #findAll(tab, thing[1]) >= thing[2] ) |
Bonus option: Say you don't want to make the tables of tables like above. E.g., you want ingredients to look like this:
1 | local required = {"foo", "foo", "bar", "bar", "bar"} |
Then we can just go through all of the elements of required and count how many times they appear!
2 | for _, thing in pairs(required) |
3 | haveAll = haveAll and ( #findAll(tab, thing) >= #findAll(required, thing) ) |
This is somewhat inefficient because it will re-check for, say, "bar" three times -- but the behavior will be correct, and this will still be very fast for small lists like ingredient lists.
