datafy
- (datafy x)
Attempts to return x as data. datafy will return the value of clojure.core.protocols/datafy. If the value has been transformed and the result supports metadata, :clojure.datafy/obj will be set on the metadata to the original value of x, and :clojure.datafy/class to the name of the class of x, as a symbol.
© Rich Hickey. All rights reserved. Eclipse Public License 1.0
3 Examples
;; default impl is the identity (datafy {:message "Hello"}) => {:message "Hello"} ;; exceptions default datafy impl is `Throwable->map` (datafy (ex-info "An Exception" {:msg "something went wrong"})) {:cause "An Exception", :data {:msg "something went wrong"} :via [{:type clojure.lang.ExceptionInfo, :message "An Exception", :data {:msg "something went wrong"}, :at [user$eval16337 invokeStatic "form-init3462716552974711523.clj" 120]}], :trace [[user$eval16337 invokeStatic "form-init3462716552974711523.clj" 120] [user$eval16337 invoke "form-init3462716552974711523.clj" 120] [clojure.lang.Compiler eval "Compiler.java" 7181] ,,, [clojure.lang.AFn run "AFn.java" 22] [java.lang.Thread run "Thread.java" 833]]}
;; add a (bogus) Datafy implementation for java.util.Date (require '[clojure.core.protocols :as p]) (require '[clojure.datafy :as d]) (extend-protocol p/Datafiable java.util.Date (datafy [d] {:type 'Date :timestamp (.getTime d)})) (d/datafy (java.util.Date.)) ;;=> {:type Date, :timestamp 1641145865991}
;; adding a data representation to a java.io.File (require '[clojure.core.protocols :as p]) (require '[clojure.datafy :as d]) (extend-protocol p/Datafiable java.io.File (datafy [f] {:exists (.exists f) :length (.length f) :last-modified (.lastModified f) :path (.toString f)}))) (d/datafy (java.io.File. "/home/alfred/todo.txt")) ;;=> {:exists true, ;; :length 28850, ;; :last-modified 1641082627553, ;; :path "/home/alfred/todo.txt"} ;; java.io.File is availiable with (:clojure.datafy/obj (meta ...))