Nexo for VS Code

Support for Nexo, the language with one way to do each thing.

• Highlighting of the whole core: keywords, pipeline steps after |>, text with {interpolation}, numbers with units (30s, 10%, 19.99 EUR), ## documentation comments.
• Errors as you type, in the same words as the compiler: what went wrong and how to fix it. Warnings of nexo lint too.
• Quick fixes for errors and warnings, and Fix all (the safe fixes of nexo fix).
• Format Document with nexo fmt (it has no options).
• Go to definition, hover with the signature and the ## comments, the outline of the file and completion.
• Commands Nexo: Run file, Nexo: Run tests of file and Nexo: Restart language server.

Installing Nexo

The extension carries no language server of its own. It runs nexo lsp, the server built into the nexo command (D87), and the two run commands run that same command in a terminal. Nothing works until nexo is installed and nexo.path points at it.

Nexo is not packaged yet, so it is installed from a clone of the repository. Either implementation serves: both answer the same requests with the same words.

git clone https://github.com/marcrabadan/nexo.git
cd nexo

Phase 0, the interpreter

Needs Python 3.12 or newer.

python3.12 -m venv .venv
.venv/bin/pip install -e '.[dev]'

The command is then <clone>/.venv/bin/nexo.

Phase 1, the compiler

Needs a Rust toolchain (cargo, 1.89 or newer) and clang.

cd compiler
cargo build --release

The command is then <clone>/compiler/target/release/nexo.

Pointing the extension at it

Open Settings (Cmd/Ctrl ,), search for nexo.path and write the absolute path of the command, or put its directory on your PATH and leave the default nexo. In settings.json:

{
  "nexo.path": "/Users/you/nexo/compiler/target/release/nexo"
}

The value is run as it is written: VS Code does not expand ${workspaceFolder}, ~ or environment variables inside it, so write the path in full. Saving the setting restarts the server, so there is nothing else to do; Nexo: Restart language server restarts it after rebuilding the compiler.

If the path is wrong, the extension says so once, naming the command it tried: Nexo: cannot start "... lsp". Set nexo.path to the nexo command. The server's own log is in the Output panel, channel Nexo.

Settings