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docs/tut/crash-course/6-table-state.md

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+# Table State
+
+Vide has functions for dealing with table states.
+
+Below is an example using the above `List` class.
+
+```lua
+type Item = {
+    Name: string,
+    Icon: number    
+}
+
+local items = source({} :: Array<Item>)
+
+List {
+    Children = indexes(items, function(item, i)
+        return create "ImageLabel" {
+            Image = function()
+                return "rbxassetid://" .. item().Icon
+            end,
+
+            LayoutOrder = i
+        }
+    end)
+}
+```
+
+Here we map each element in `items` to a value returned by a callback.
+
+The callback is called only *once* per key. The first argument given to the
+callback is a state that has the value of the table key's value.
+
+Anytime the value of the corresponding table key changes, the state value
+changes too. This saves us from having to recreate a UI element any time a
+table index changes.