To deal a single card from a deck, we might use the following dfn:
deal ← { (?≢⍵) I ⍵ }
deck ← ↑,⍳13 4 disp deal deck 7♢
We can do the same tacitly using a fork and a jot:
deal ← ?∘≢ I ⊢
disp deal deck 4♡ ↓disp 5 deal deck 9♡ J♣ K♢ 2♡ T♠