Will learning about it, I got really confused about it. All I'm just asking is how to use.
✓ ANSWER ACCEPTED
How does the second parameter of table.sort (comp) work?
2 answers
✓ Accepted answer
The second parameter of table.sort() is called a comparator function. It is called with two arguments representing two elements from the array and the comparator function is supposed to return a bool (truthy/falsey value) representing whether or not the first element should go after the second element. Because functions are first class values in Lua, you can simply pass in a function in the parameter list like any other value. Here are a few examples:
--Sort numbers in ascending order
local table1 = {3 , 4 , 2 , 1 , 4}
table.sort(table1 , function(a , b)
return a < b
end)
--Note: equivalent to table.sort(table1) because the default comparator is used
--Another slightly less trivial example
--Sorts the leaderboard points in descending order
local leaderstats = {
{Name = "Player1"; Points = 100};
{Name = "Player3"; Points = 300};
{Name = "Player5"; Points = 200};
{Name = "RayCurse"; Points = 500};
{Name = "iofkl"; Points = 600};
}
table.sort(leaderstats , function(a , b)
return a.Points > b.Points
end)
I can recommend looking at lua-users.org. The comp parameter is a function that takes 2 arguments and returns true if the first one should be sorted before and vice versa. Example:
t = { 3,2,5,1,4 }
table.sort(t, function(a,b) return a>b end)
-- The table will now look like this { 5,4,3,2,1 }
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6 comments
So basically if it returns true, a will be first?
Yes, if it returns true a will be placed before b, the condition can be anything.
And if false then b will be placed first?
Correct
table.sort sorts the table in place so there is no need to reassign the variable.
Ah yes, my bad. You are correct, will fix the code example.