Patcher

Use REST inside your Clojure programs. Represent an edit to a data structure as a data structure (patch) and apply it to any nested combination of maps, lists, vectors and sets.

Installation

Add this to project.clj (if you use Leiningen)

[patcher "0.1.3"]

or this to deps.edn (if you don't)

{patcher {:mvn/version "0.1.3"}}

Usage

First things first, let's get imports and namespaces off our chest.

(require '[patcher.core :refer [apply-patch]])

Then fire up the REPL, type a definition in-o:

(def patch {:type :put :path [:some :keys] :value "A new value"})

And apply it to a thing-o

(apply-patch patch {:some {:keys "An old value"} :other {:keys "I am a value too, y'know"}})
=> {:some {:keys "A new value"} :other {:keys "I am a value too, y'know"}}

Apply it to a thing-o

(apply-patch {:type :post :path [:interests] :value :music} {:age 35 :sex :male :interests [:cooking]})
=> {:age 35 :sex :male :interests [:cooking :music]}

A patch is a map with 3 keys: :type, :path and :value. :type can be :put, :post, :delete or :merge.

:put will replace whatever value you would get with (get-in coll path) with value :post is similar, but it will insert (conj) value into the existing sequence instead of replacing it :merge assumes that value is a map or a sequence and replaces a map or a sequence at path with a concatenation (merger) of it and value :delete will purge it from the data structure so that (get-in coll path) returns nil

License

Copyright © 2018 Skolkovo Institute of Science and Technology

Distributed under the Eclipse Public License either version 1.0 or (at your option) any later version.