error.clj

(ns typed.test.person
  (:require [typed.core 
             :refer [check-ns cf ann-datatype ann
                     tc-ignore ann-protocol AnyInteger]]))

(ann-protocol Age 
  :methods
  {age [Age -> AnyInteger]})
(tc-ignore
(defprotocol Age
  (age [this]))
)

(ann-datatype Person 
  [(name :- String)
   (age :- AnyInteger)])
(deftype Person [name age]
  Age
  (age [this] age))


(age (Person. "Lucy" 34))

(ann my-apply (All [x y] [[x -> y] x -> y]))
(defn my-apply [f a]
  (f a))

(my-apply age nil)

;; REPL
; error messages for polymorphic function applications now have:
; - line number (and column if using Clojure 1.5.0-beta1)
; - expected domain types
; - actual argument types
; - macroexpanded original form

typed.test.person=> (check-ns)
#<Exception java.lang.Exception: 28: Polymorphic function typed.test.person/my-apply could not be applied to arguments:
Domains: 
(Fn [x -> y]) x
Args:
(Fn [typed.test.person/Age -> (U java.lang.Integer java.math.BigInteger java.lang.Byte java.lang.Short clojure.lang.BigInt java.lang.Long)]) nil

in: (typed.test.person/my-apply typed.test.person/age nil)>
typed.test.person=>