Piton for VS Code

Syntax highlighting from a TextMate grammar, and everything else from the language server.

Installing

The extension needs the piton binary on PATH. On macOS or Linux:

curl -fsSL https://github.com/piton-lang/piton-rs/releases/latest/download/install.sh | sh

On Windows, in PowerShell:

irm https://github.com/piton-lang/piton-rs/releases/latest/download/install.ps1 | iex

Or build it from a checkout of the repository with cargo xtask install.

Then install Piton Language from the Extensions view.

From a checkout

From this directory:

npm install
npm run package
code --install-extension piton-lang-*.vsix

Or symlink this directory into ~/.vscode/extensions/piton for development.

Versions

The extension's version is the Piton release it goes with: extension 0.1.41 is for Piton 0.1.41. To publish for a new release:

npm run version:sync -- 0.1.42
npm run publish

With no argument, version:sync works out the Piton version from Cargo.toml and the commit count, as the edge release does.

What comes from where

The TextMate grammar colours tokens. Diagnostics, completion, hover, go-to-definition, find-references, rename, symbols, semantic highlighting, inlay hints, code actions, formatting, folding, and selection ranges all come from piton lsp, because they need the resolved program rather than the text.

Set piton.server.path if the binary is not on PATH, or piton.server.enabled to false to use highlighting alone.

piton.formatOnSave formats the document before it is saved — the autoFormatOnSave option. It is false unless you turn it on. The formatter adds the space after // and touches nothing else that is commented.

Enter on a colon line (a declaration, or a dictionary or anchor property with nothing after its colon) lands one level in; Enter on a blank line inside a dictionary or anchor lands one level back. Both are onEnterRules in language-configuration.json. A list item or a merge line never opens a block, even when it ends in a colon (- Settings: is just a string), and Enter does not continue a list by itself. The language server answers the same two moves through on-type formatting if you turn on editor.formatOnType.

The blank-line rule reads the whitespace VS Code leaves on the line it just indented, so it applies while you are typing. A blank line with no whitespace at all (one already in the file, or after editor.trimAutoWhitespace removed it) gives the rule nothing to measure; editor.formatOnType covers that case through the server.

Commands

A compiled file has to exist on disk for the first two; build the project first.