/Prelude-v21.1.0/NonEmpty/concat.dhall

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Concatenate a NonEmpty list of NonEmpty lists into a single NonEmpty list

Examples

  concat
Natural
{ head = { head = 0, tail = [ 1, 2 ] }
, tail = [ { head = 3, tail = [ 4 ] }, { head = 5, tail = [ 6, 7, 8 ] } ]
}
≡ { head = 0, tail = [ 1, 2, 3, 4, 5, 6, 7, 8 ] }
  concat
Natural
{ head = { head = 0, tail = [] : List Natural }
, tail =
[ { head = 1, tail = [] : List Natural }
, { head = 2, tail = [] : List Natural }
]
}
≡ { head = 0, tail = [ 1, 2 ] : List Natural }
  concat
Natural
{ head = { head = 0, tail = [] : List Natural }
, tail = [] : List (NonEmpty Natural)
}
≡ { head = 0, tail = [] : List Natural }

Source

{-|
Concatenate a `NonEmpty` list of `NonEmpty` lists into a single `NonEmpty`
list
-}
let NonEmpty =
./Type.dhall sha256:e2e247455a858317e470e0e4affca8ac07f9f130570ece9cb7ac1f4ea3deb87f
? ./Type.dhall

let NonEmpty/toList =
./toList.dhall sha256:0977fe14b77232a4451dcf409c43df4589c4b3cdde7b613aab8df183be1b53f5
? ./toList.dhall

let List/concatMap =
../List/concatMap.dhall sha256:3b2167061d11fda1e4f6de0522cbe83e0d5ac4ef5ddf6bb0b2064470c5d3fb64
? ../List/concatMap.dhall

let concat
: ∀(a : Type) → NonEmpty (NonEmpty a) → NonEmpty a
= λ(a : Type) →
λ(xss : NonEmpty (NonEmpty a)) →
{ head = xss.head.head
, tail =
xss.head.tail
# List/concatMap (NonEmpty a) a (NonEmpty/toList a) xss.tail
}

let example0 =
assert
: concat
Natural
{ head = { head = 0, tail = [ 1, 2 ] }
, tail =
[ { head = 3, tail = [ 4 ] }, { head = 5, tail = [ 6, 7, 8 ] } ]
}
≡ { head = 0, tail = [ 1, 2, 3, 4, 5, 6, 7, 8 ] }

let example1 =
assert
: concat
Natural
{ head = { head = 0, tail = [] : List Natural }
, tail =
[ { head = 1, tail = [] : List Natural }
, { head = 2, tail = [] : List Natural }
]
}
≡ { head = 0, tail = [ 1, 2 ] : List Natural }

let example2 =
assert
: concat
Natural
{ head = { head = 0, tail = [] : List Natural }
, tail = [] : List (NonEmpty Natural)
}
≡ { head = 0, tail = [] : List Natural }

in concat