Card question in clojure

foo.card-q.clj

(ns foo.card-q)

(def deck
  "Given a set of cards, return a deck of those cards"
  vector)

(def card
  "Given a map of card properties, return a card with those properties"
  identity)

(def shuffle-deck
  "Given a deck, return a new deck with the cards in a random order"
  shuffle)

(def combine-decks
  "Given 1+ decks, return a new deck with all of the cards from all decks"
  concat) ; or (comp doall concat) if you want eagerness