A WebAssembly based playground for Janet (https://janet-lang.org) like that of https://play.golang.org

Intended to enable sharing of "runnable" example code in the Janet community.

Currently the janet.wasm artifact produced here is used by the "playground" functionality in JanetDocs

You must ensure that you have installed emscripten (emsdk) > 2.0 and that it is in your path and executable. (Generally you have to do something like source ./emsdk_env.sh in the emsdk install directory.)

Then:

jpm install https://github.com/MikeBeller/janet-playground.git
./playground update-janet v1.16.0 # or whatever release version you want
./playground build
./playground install
./playground serve  # starts a server on localhost:8000

Then point your browser to http://localhost:8000/ to try it out.

After building as per above copy janet.wasm and janet.js from the public/js directory of this repository to the public/playground directory of the janetdocs repository.

Q: How does this relate to the web repl on https://janet-lang.org?

A: The web repl on janet-lang.org, as currently constituted, can only be used for use case "A" above. And even there, because it doesn't allow multi-line editing, it's difficult to use for any larger examples. That said, the janet-lang.org web repl does permit sequential execution of Janet forms, with subsequent forms operating on the same running fiber as the previous forms. By contrast, janet-playground creates an interpreter, runs the example, and then de-inits janet.

The playground UI is styled based on the go playground, and uses it's style sheet static/style.css . As such, portions of this code may be Copyright (C) 2014 The Go Authors. See: https://github.com/golang/playground