Clojure for Beginners: Clojure Vectors — Create, Access, Grow & Inspect

Clojure Vectors — Create, Access, Grow & Inspect

Phase 2 begins! Vectors are the everyday workhorse of Clojure — ordered, indexed, immutable. In this episode we create vectors, access them by index, grow them with conj, peek at the last item, and pop it off. We also discover that vectors double as functions of their own index.

Code

;; Episode 7: Vectors
;; Clojure for Beginners in Neovim

;; Create a vector with literal syntax
(def colors ["red" "green" "blue"])
(println "Colors:" colors)

;; Access by index — get and nth
(println "First:" (get colors 0))
(println "Third:" (nth colors 2))

;; Count returns how many items
(println "Count:" (count colors))

;; conj adds to the end of a vector
(def more-colors (conj colors "yellow"))
(println "After conj:" more-colors)

;; Vectors are immutable — the original is unchanged
(println "Original:" colors)

;; peek and pop — last item and everything but last
(println "Peek:" (peek more-colors))
(println "Pop:" (pop more-colors))

;; Vectors work as functions of their index
(println "colors at 1:" (colors 1))

;; A shopping list example
(def cart ["apples" "bread" "milk"])
(def cart (conj cart "eggs"))
(def cart (conj cart "cheese"))
(println "Cart:" cart)
(println "Items:" (count cart))

Key Points

Watch the video above for a full walkthrough — every keystroke is shown so you can code along.

Student code: GitHub