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;'<<SPEC'

<!--
Copyright (c) 2012-2024, Chris Pressey, Cat's Eye Technologies.
This file is distributed under a 2-clause BSD license.  See LICENSES/ dir.
SPDX-License-Identifier: LicenseRef-BSD-2-Clause-X-Robin
-->

### `last` ###

    -> Tests for functionality "Evaluate Robin Expression (with List)"

`last` evaluates its first argument to obtain a non-negative integer,
considered to be a desired length, and its second argument to obtain a
list.  It then evaluates to the suffix of the given list of the desired
length.

    | (last 0 (list 1 2 3 4 5))
    = ()

    | (head (last 1 (list 1 2 3 4 5)))
    = 5

    | (last 3 (list 1 2 3 4 5))
    = (3 4 5)

    | (last 6 (list 1 2 3 4 5))
    ? abort (expected-list ())

    | (last 1 (literal foo))
    ? abort (expected-list foo)

Unlike `first`, `last` does care if it's not a list, even when the count
is zero.

    | (last 0 (literal foo)))
    ? abort (expected-list foo)

'<<SPEC'

(define last (fun (n li)
  (reverse (first n (reverse li)))))