Canon for Visual Studio Code

Language support for Canon — a programming language that compiles directly to WebAssembly components.

Features

Syntax highlighting for .can files (TextMate grammar)
Diagnostics as you type: lex errors, parse errors, sort-order violations, and type-check errors
Hover documentation for built-in types and well-known constructors
Go to definition
Formatting via canon fmt (enable format-on-save for the canon language to get auto-sorted declarations)

All language features are powered by the compiler's built-in language server (canon lsp) — there is no separate LSP binary to install.

Getting the `canon` binary

The extension resolves the compiler in this order:

The canon.serverPath setting, if set
canon on your PATH
~/.cargo/bin/canon
A previously downloaded binary

If none is found, the extension offers to download a prebuilt binary from GitHub releases automatically. You can also trigger this manually with the Canon: Download Language Server command, or install the compiler yourself:

curl -fsSL https://raw.githubusercontent.com/Almaju/canon/main/install.sh | sh

Settings

Setting	Description
`canon.serverPath`	Explicit path to the `canon` binary
`canon.trace.server`	LSP trace level (`off` / `messages` / `verbose`)

Commands

Command	Description
Canon: Restart Language Server	Restart `canon lsp`
Canon: Download Language Server	Fetch the latest prebuilt binary from GitHub releases

About Canon

Canon presents a small surface area — no let, no if/else, no comments, no local variables. Branching is dispatch on a union. Effects are passed as capabilities. Wherever ordering is discretionary, the compiler enforces alphabetical order.

Bool = False + True
User = Birthday * Username

main = () -> Unit {
    "hello".print()
}

See the language guide for more.

Canon

Almaju