{-
Tag each element of the list with its index

Examples:

```
./indexed Bool [ True, False, True ]
=   [   { index = 0, value = True  }
    ,   { index = 1, value = False }
    ,   { index = 2, value = True  }
    ] : List { index : Natural, value : Bool }

./indexed Bool ([] : List Bool)
= [] : List { index : Natural, value : Bool }
```
-}
    let indexed
        : ∀(a : Type) → List a → List { index : Natural, value : a }
        = List/indexed

in  indexed