; dicts
(func dict? (val)
    (and
        (list? val)  ; TODO should this be automatic?
        (or
            (eq? 0 (list-length val))
            (and
                (eq? 1 (list-length val))
                (list? (first val)))
            (apply and (map list? val)))
        (eq? 0 (list-length (filter (lambda (x) (not (eq? x 2))) (map list-length val))))))

(type :dict :list dict?)

(func dict () (list))

(func has? (in :dict key)
    (not (empty?
        (filter (lambda (x) (eq? (first x) key)) in))))

(func get (d :dict key)
    (first (rest (first
        (filter (lambda (x) (eq? (first x) key)) d)))))

(func set (d :dict key val)
    (if (has? d key)
        (map (lambda (x) (if (eq? key (first x)) (list (first x) val) x)) d)
        (append d (list key val))))

(func keys (d :dict) (map first d))

(func drop (d :dict key)
    (filter (lambda (x) (not (eq? (first x) key))) d))