What is the best way to clear out all entries in a Dictionary?
I have some code that will overwrite on an as-needed basis for MANY dictionary entries. Is this the correct way to go about this if I want to make sure all memory is released for the entries:
--Script
local module = require(script.ModuleScript)
local done = module.Add()
local myTable = module.Table()
function removeTable()
for i, v in pairs(myTable) do
print(i,v)
end
myTable = module.Table(true)
print("---table removed checking---")
for i, v in pairs(myTable) do
print(i,v)
end
print("---table checking done ---")
end
removeTable()
done = module.Add()
for i,v in pairs (myTable) do
print(i,v)
end
. .
--Module Script
local module = {}
local theTable = {}
function module.Add()
local counter = 0
local temp = ""
while counter < 3 do
counter = counter + 1
temp = tostring(counter)
theTable[temp] = true
end
return (theTable)
end
function module.Table(valueIn)
if valueIn == true then
theTable = {}
end
return (theTable)
end
return module
--[[ Output
1 true
3 true
2 true
---table removed checking---
---table checking done ---
1 true
3 true
2 true
--]]
It looks like it works how I want it to, but I'm still learning and I really don't want to deal with a problem later on.
0
2 answers
There are two ways of doing this, redefining it as an empty table or using a generic for loops to essentially remove each entry
Ex1, redefining as an empty table:
local dict = {oof = "ree", Ding = "Pong"}
print(dict.oof)--"ree"
dict = {}
print(dict.oof)--nil
Ex2, generic for loop
local dict = {oof = "ree", Ding = "Pong"}
print(dict.oof)--"ree"
for k in next,dict do
dict[k] = nil
end
print(dict.oof)--nil
Hopefully this helped you out
0
What you are doing is creating a new table when you run module.Table(true) this means that anything held within the last table can be used.
Example
local tblModule = require(script.ModuleScript) local tbl1 = tblModule.Table() local tbl2 = tblModule.Table(true) print(tbl1 == tbl2) -- false
This can cause a lot of problems if two scripts use this same module they could end up with different tables being used.
The valid method of clearing a index is to set its value to nil tbl1["2"] = nil. So your clear function should loop through the table and set the key to nil.
function module.Table(valueIn)
if valueIn == true then
for i, _ in pairs(theTable) do
theTable[i] = nil
end
end
return theTable -- parentheses are not needed here
end
The second problem is with your Add function as running it again will have 0 effect on the table as the counter is not stored. You should also use a numeric for loop as well.
local counter = 0 local addAmount = 3 local theTable = {} function module.Add() for i=1, addAmount do theTable[tostring(counter +i)] = true end counter = counter + addAmount end
You would also need to reset the counter when you clear the table.
Hope this helps.