Union Types (Algebraic Data Types) for Clojure and ClojureScript, based on clojure.spec.
Provides a case-of macro, which does case matching based on which branch in an
or spec a value conforms to.
case-of checks at compile time that all cases are handled, and if not throws an exception.
To install, add the following dependency to your project or build file:
[lambdaisland/uniontypes "0.2.0"](require '[lambdaisland.uniontypes :refer [case-of]])
(s/def ::availability (s/or :sold-out #{:sold-out}
:in-stock pos-int?
:reordered (s/tuple pos-int? pos-int?)
:announced string?))
(defn display-status [availability]
(case-of ::availability availability
:sold-out _
"Sold out."
:in-stock amount
(str "In stock: " amount " items left.")
:reordered [min max]
(str "Available again in " min " to " max "days" )
:announced date
(str "Available on " date ".")
:spec/invalid msg
(str "Not a valid availability: " msg)))Copyright © 2016-2017 Arne Brasseur
Distributed under the Mozille Public License 2.0