Dustin Getz dustingetz

Multiplayer chat with presence – Electric Clojure

60 LOC: demo_chat_exdended.cljc

20230131.presence.edited.mp4

Missionary concept map

Missionary primitives fit into three categories:

Effect descriptions = pure functional programming which is about trees not graphs

continuous flow, m/?< (switch)
m/watch, m/latest, m/cp
m/observe
m/reductions, m/relieve

PostgreSQL hello world — Electric Clojure

How do I integrate a SQL database backend?

Easy:

make an ordinary Clojure function query-pokemon-list for the query
The query is blocking, and Electric Clojure is async, so use e/offload to move it to a thread pool.
- (Don't block the event loop!)
e/offload throws Pending until the query finishes, and then the exception "goes away"

Datomic web explorer

Client API, tested on Datomic Cloud
database entity browser
server paginated infinite scroll
streaming information model - displays incremental resultsets as they become available (useful for slow queries)
automatic backpressure and cancellation of abandoned queries
custom web renderers with dynamic queries

Code is not optimized yet – we are still learning the idioms.

HOWTO install `#user/uri` reader extension in Clojure/Script

We use #user/uri rather than unquaified #uri per Alex Miller comment in the Ask Clojure thread.

License: public domain

List of Photon demos and content

Photon is a network-transparent Clojure/Script dialect for full-stack web application development. It uses macros to let you interweave client and server code in a single .CLJC file, so you can define a full-stack frontend/backend webapp all in one place. Photon is designed for stateful full-stack web applications with complex frontend/backend data sync requirements.

Newest demos:

Datomic web explorer (Oct 2022)

Personal favorites:

Photon infinite scroll over node_modules v2

Datomic database transaction browser coded in Photon, by nottmey

This fullstack web app is 239 LOC in a single file, coded with just fns in the straightforward/easy style of PHP. All client/server I/O is managed!

It took him 10 hours. Thank you Malte! #Clojure

20220529.Photon.Datomic.Viewer.-.Malte.Nottmeyer.mp4

React.js interop POC — Electric Clojure

80 LOC: demo-reagent-interop.cljc (25 LOC for adapter)

20220729.photon.reagent.react.interop.mp4

Proof of client/server transfer — Electric Clojure

Electric Clojure lets you code frontend/backend expressions that compose across the client/server boundary, due to compiler-managed network powered by DAGs. #Clojure

20230131.hello.photon.tranasfer.2.edited.mp4

p/defn defines a function that follows all the same laws as regular Clojure functions, but it’s actually a macro that compiles the function body into a DAG (Directed Acyclic Graph).

	(defmacro future
	"Takes a body of expressions and yields a future object that will
	invoke the body in another thread, and will cache the result and
	return it on all subsequent calls to deref/@. If the computation has
	not yet finished, calls to deref/@ will block, unless the variant of
	deref with timeout is used. See also - realized?."
	{:added "1.1"}
	[& body] `(future-call (^{:once true} fn* [] ~@body)))

	(defn future-call