Inspecter

Clojure library offering a few helpful extensions to the popular Specter for selecting and transforming Hiccup data using simple CSS selectors.

Installation

First add Specter as a dependency to your project. Then add the following dep to your project or deps file:

Usage

First be sure to include the relevant libraries:

(require '[com.rpl.specter :as specter])
(require '[inspecter.core :as i])

select

Find a Hiccup element by its id:

(def hiccup
  [:div
   [:h1#zero "My Title"]
   [:h2#one {:data-attr "one"} "Hello"]
   [:h2#two {:data-attr "two"} "World"]])

user=> (specter/select [(i/matches "#two")] hiccup)
[[:h2#two {:data-attr "one"} "World"]]

Specter's select function returns a vector of ALL items that match the selector.

Push it a little further and grab the attribute maps for every h2:

user=> (specter/select [(i/matches "h2") i/ATTRS] hiccup)
[{:data-attr "one"}
 {:data-attr "two"}]

transform

Most importantly, though, is Specter's ability to navigate to items in collections and update them in place. This library makes updating Hiccup in place easy:

(def hiccup
  [:div
   [:h1 "My Title"]
   [:h2.find-me "My Subtitle"]])

user=> (specter/transform
         [(inspect/matches ".find-me") inspect/ATTRS]
         (inspect/update-attrs #(assoc % :changed :me))
         hiccup)
[:div
 [:h1 "My Title"]
 [:h2.find-me {:changed :me} "My Subtitle"]]

Complete Function List

Inspecter exposes the following functions for Hiccup path navigation and transformation:

• inspecter.core/matches - Returns a recursive path navigator
• inspecter.core/ATTRS - Path navigator to an element's attributes.
• inspecter.core/CONTENTS - Path navigator to an element's contents.
• inspecter.core/update-attrs - Helper for updating an element's attributes.

CSS Selectors

Inspecter matches Hiccup elements via simple, limited-scope CSS selectors. While the universe of potential CSS selectors is enormous, Inspecter implements a narrow set for tag, id, and class matching. These are each supported:

• * - Matches every element
• div - Matches all [:div ...] elements
• nav#main - Matches all [:nav {:id "main"} ...] or [:nav#main ...]
• div.small.button - Matches all [:div.small.button] or [:div {:class "small button"} ...] elements
• div[hello=world] - Matches all [:div {:hello "world"} ...] elements

License

Distributed under the MIT License.