Skip to content

Latest commit

 

History

History
90 lines (73 loc) · 3.88 KB

Readme.md

File metadata and controls

90 lines (73 loc) · 3.88 KB
Raw

Hyperfiddle Photon – a multi-tier Clojure/Script dialect for fullstack web apps with managed server data-fetching

Photon lets you express a frontend/backend web application as a single unified Clojure/Script expression that transcends the client/server boundary.

(p/defn Teeshirt-orders [db]
  (p/client
    (dom/div
      (let [!email (atom "") email (p/watch !email)]
        (ui/input {::ui/input-event (p/fn [e] (reset! !email (:value dom/node)))})
        (dom/h1 "Your tee-shirt orders")
        (dom/table
          (p/server
            (p/for [x (query-teeshirt-orders db email)]
              (p/client (dom/tr (pr-str x))))))))))

It's called Photon because every point in a Photon form can be thought of as simultaneously a reactive flow and a value.

Albert Einstein, on the wave-particle duality: "It seems as though we must use sometimes the one theory and sometimes the other, while at times we may use either. We are faced with a new kind of difficulty. We have two contradictory pictures of reality; separately neither of them fully explains the phenomena of light, but together they do."

Setup and healthcheck

git clone ...
yarn                        # for codemirror or something, todo remove
cd photon
clj -A:dev -X user/main     # healthcheck app http://localhost:8080
  • dev alias
  • (user/main) compiles assets and serves app

Examples

  • see src-docs/user/ for demos and tutorials
  • Start a JVM REPL under :dev alias and jack-in in your usual wayl; (user/main)
  • App entrypoint: src-dev/user.clj, user.cljs

Please ask questions in slack so we can turn them into examples!

IDE setup

Cursive:

  • new deps.edn project from existing sources
  • dev alias
  • Add Configuration
    • new Clojure REPL - Local
    • run with Deps
    • alias: dev
  • Run configuration

Emacs:

  • C-u M-x cider-jack-in-clj
  • append ":dev" to end of the command string like "-M:cider/nrepl:dev"

Project status = private technical alpha

Updated: 2022 August 9

Current focus is TodoMVC and odopms

  • Photon core language at CLJ REPL
  • Photon core language at CLJS REPL [x] Cursive [x] Emacs [x] Calva
  • Photon client/server transfer [x] Cursive [x] Emacs [x] Calva
  • Photon-dom basic tutorial level usage (bugs allowed)
  • Photon-dom hot code reloading - [x] Cursive, [x] Emacs, [x] Calva
  • Photon-dom webview with client/server transfer (read only)
  • Concurrent sessions/tabs with shared server state
  • Photon-dom controlled text input [*] stabilized for network latency
  • TodoMVC [x] client/server transfer
  • client/server transfer stress tests
  • Photon/Missionary interop
  • [*] 7 GUIs
  • [*] pending states and error handling - robust idioms
  • tee-shirt orders example app with select options
  • HFQL spec-driven forms with user interaction and staging area

Known issues, feature gaps, gotchas

Updated: 2022 August 9

  • no clojure.core/fn yet inside Photon blocks, it's coming. Use partial for now
  • no fn destructuring yet, no variable fn arity yet
  • no recursion yet - see workaround in demo_7_explorer.cljc
  • no interop special forms in Photon blocks, including no js/ access

Errors

  • Cursive says Dependency cycle: hyperfiddle.api -> hyperfiddle.hfql -> hyperfiddle.hfql.impl -> hyperfiddle.api – Cursive is not correctly handling Clojure 1.11 :as-alias, load the file form by form instead
  • :eval opcode - probably interop syntax, or a macro like assert that expands to interop syntax
  • Unbound var. Usually means wrong peer, i.e. accessed server-only var on client

References