core.clj

(ns core-typed-tests.core
  (:require [clojure.core.typed :as t]
            [clojure.core.typed.async :as ta]
            [clojure.core.async :as a]))

(t/typed-deps clojure.core.typed.async)

(t/ann foo [-> nil])
(defn foo []
  (a/alts!! [(a/chan) (a/chan)] :priority true)
  nil)

(comment
  "the annotation for alts!!, according to cf"
  (All [x d]
       (Fn
         [(t/Seqable (U (ta/Port x) [(ta/Port x) x]))
          (t/Seqable (ta/Port x))
          & {:priority (U true nil)} :mandatory {:default d}
          -> (U [x (ta/Port x)] [d (Value :default)])]
         [(t/Seqable (U (ta/Port x) [(ta/Port x) x]))
          & {:priority (U true nil)}
          -> [x (ta/Port x)]]))
  )

repl

core-typed-tests.core=> (t/check-ns)
Start collecting core-typed-tests.core
Start collecting clojure.core.typed.async
Finished collecting clojure.core.typed.async
Finished collecting core-typed-tests.core
Collected 2 namespaces in 225.22 msecs
Start checking clojure.core.typed.async
Checked clojure.core.typed.async in 252.916 msecs
Start checking core-typed-tests.core

ExceptionInfo Internal Error (core-typed-tests.core:10:3) Uneven number of keyword arguments provided to polymorphic function with keyword parameters.  clojure.core/ex-info (core.clj:4327)
core-typed-tests.core=>