EWC

Note

ewc and ewc-client are now one repository. Everything lives here in Dyalog/ewc: the APL implementation in EWC/, the React client in client/

EWC ("Everywhere Window Create") is a cross-platform implementation of Dyalog APL's ⎕WC GUI family, currently a growing subset of ⎕WC's functionality.

It lets a ⎕WC application run outside Windows - on Linux, macOS or Windows - either in a desktop window or in a browser. The supported subset grows with the needs of early adopters; see the object reference to check what is covered.

Status: EWC is under active development and not yet supported through normal Dyalog channels.

Documentation: the EWC User Guide covers installation, configuration, and a reference page for every supported class.

Requirements

• Dyalog APL Unicode 18.2 or later
• Desktop mode needs the HTMLRenderer - currently Linux, macOS and Windows
• Browser modes run on any Dyalog-supported platform
• Only to build the client from source: Node.js and Yarn 1 (classic) - install guide. A release download needs neither; see Quick start below.

Quick start

Just want to use EWC? A release is self-contained - no Node.js, no yarn, no build step. Three steps:

1. Download and unpack the ewc-vX.Y.Z.zip asset from the latest release.

   Take that named asset, not GitHub's auto-generated "Source code" archive. The built client isn't committed to the repository, so only ewc-vX.Y.Z.zip runs.

2. Start Dyalog APL and link the two APL directories:

    ]link.create #.EWC /path/to/ewc/EWC
    ]link.create #.demo /path/to/ewc/test-apps/demo
   

3. Run the demo:

    demo.Run 'Desktop'
   

   You get a form with a dropdown of sample applications (about 100 of them). The source for each is the function demo.DemoXXX, where XXX is the name in the dropdown.

Then build your own:

EWC.Init 'Desktop'
'F1' eWC 'Form' 'Hello World' (10 10) (400 600)

EWC.Init creates eWC, eWS, eWG, eWN, eNQ, eEX and eDQ in the calling namespace - EWC's workalikes for ⎕WC, ⎕WS, ⎕WG, … They reimplement the same interface rather than wrapping the system functions, so you call them instead of, not alongside, the originals. A left argument changes the prefix ('x' EWC.Init 'Browser' gives xWC, xWS, …).

Using ]link.import instead of ]link.create (or running without .NET / a file system watcher)? Also set EWC.FOLDER←'/path/to/ewc'.

Developing EWC

Building the client from source is the only reason you need Node.js and yarn:

git clone https://github.com/dyalog/ewc.git
cd ewc
yarn install     # installs the workspace: root tooling + client/
yarn build       # → client/dist, which the server serves

Then link and run exactly as in Quick start above. Every yarn command runs from the repository root - there is no need to cd client.

Link the two APL directories, not the repository root. Link maps directory names to APL names, and once client/node_modules exists npm package names collide (acorn-jsx with acorn, eslint-scope with eslint), which aborts the whole link.

See CONTRIBUTING.md for the full development workflow.

Releases

Releases are tagged vX.Y.Z and published on the releases page; the notes for each one live in RELEASES.md.

Every release ships an ewc-vX.Y.Z.zip asset containing the APL server and a prebuilt copy of the React client in client/dist/, so a release is self-contained - no Node.js and no build step to use EWC. The built client is deliberately not committed to the repository; it is produced by the Release workflow.

Modes

EWC.Init (and demo.Run) take the mode as a right argument:

Mode	Behaviour
'Desktop'	Each form gets its own HTMLRenderer window - closest to ⎕WC.
'Browser'	The server serves the client and listens on port 22322 (configurable); one browser session, so effectively a single form.
'Multi'	Experimental. Multiple browser sessions; the application namespace is cloned per connection (demo_1, demo_2, …) so each has its own state. Requires the e prefix, and an Initialise function to build the GUI per session.

Documentation

The EWC User Guide is the full documentation. Useful starting points:

• Installation and initialisation
• Configuration - port, folders, resources, logging
• Supported classes - per-class properties and events
• EWC versus ⎕WC - known differences and limitations

If you are new to ⎕WC itself, start with the standard Dyalog GUI documentation; the EWC docs only describe where EWC differs.

Repository layout

EWC is one repository with two halves that talk over a WebSocket (port 22322 by default):

Path	What it is
EWC/	The APL server - implements the eWC family and owns each class's property and event contract. Link this with ]link.create #.EWC <repo>/EWC.
test-apps/demo/	The demo application (~100 examples), also what the e2e suite drives.
docs/	This User Guide, published to https://dyalog.github.io/ewc/.
client/	The frontend - a JavaScript/React app that renders the GUI objects the server describes and reports user events back. Builds to client/dist/.
e2e/	Playwright tests, driving the demos through the real client.

Not to be confused with eWC - EWC's workalike for ⎕WC, which EWC.Init creates in your namespace.

All JavaScript tooling is a yarn workspace rooted at the repository root, so yarn install, yarn build and the test commands all run from there - there is no need to change directory into client/.

Contributing

See CONTRIBUTING.md for how the project fits together and the conventions we follow. Development happens on main; open pull requests against main.

Licence

MIT (Dyalog Ltd.) - see LICENSE.