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.cursor/rules/vide/tut/crash-course/10-cleanup.md

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+# Cleanup
+
+Sometimes you may need to do some cleanup when destroying a component or after
+a side-effect from a source update. Vide provides a function `cleanup()` which
+is used to queue a callback for the next time a reactive scope is rerun or
+destroyed, or when a stable scope is destroyed.
+
+```luau
+local root = vide.root
+local source = vide.source
+local effect = vide.effect
+local cleanup = vide.cleanup
+
+local count = source(0)
+
+local destroy = root(function()
+    effect(function()
+        local x = count()
+        cleanup(function() print(x) end)
+    end)
+
+    cleanup(function() print "root destroyed" end)
+end)
+
+count(1) -- prints "0"
+count(2) -- prints "1"
+destroy() -- prints "2" and "root destroyed"
+```
+
+::: tip
+Roblox instances do not need to be explicitly destroyed for their
+memory to be freed, they only need to be parented to `nil`. So there is no
+need to use `cleanup()` to destroy instances. However, be wary of connecting
+a function that references an instance to an event from the same instance,
+this causes the instance to reference itself and never be freed. In such a case
+you would need to use `cleanup()` to disconnect this connection or to explicitly
+destroy the instance.
+:::