core-typed-snippets.clj

; ~/.lein/profiles.clj
{:user {:plugins [[lein-typed "0.3.1"]]}}

; Run "lein new app"
; app/project.clj
(defproject app "0.1.0-SNAPSHOT"
  #_...
  :dependencies [[org.clojure/clojure "1.6.0"]
                 [org.clojure/core.typed "0.2.84"]]
  #_...)

; Run "lein deps" to install libraries

; ref. https://github.com/clojure/core.typed
(ns app.core
  (:require [clojure.core.typed :refer [ann ann-form check-ns cf]]))
(require '[clojure.core.typed :refer [ann ann-form check-ns cf]])

(ann f [Number -> Number])
(defn f [x] (inc x))

(check-ns)

(ns app.core
  (:require [clojure.core.typed :as t]))
(require '[clojure.core.typed :as t])

(t/ann f [Number -> Number])
(defn f [x] (inc x))

(t/check-ns)