/Prelude-v21.1.0/Natural/enumerate.dhall

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Generate a list of numbers from 0 up to but not including the specified number

Examples

enumerate 10 ≡ [ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 ]
enumerate 0 ≡ ([] : List Natural)

Source

{-|
Generate a list of numbers from `0` up to but not including the specified
number
-}
let enumerate
: Natural → List Natural
= λ(n : Natural) →
List/build
Natural
( λ(list : Type) →
λ(cons : Natural → listlist) →
List/fold
{ index : Natural, value : {} }
( List/indexed
{}
( List/build
{}
( λ(list : Type) →
λ(cons : {} → listlist) →
Natural/fold n list (cons {=})
)
)
)
list
(λ(x : { index : Natural, value : {} }) → cons x.index)
)

let example0 = assert : enumerate 10 ≡ [ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 ]

let example1 = assert : enumerate 0 ≡ ([] : List Natural)

in enumerate