nickel/lsp/README.md

Nickel Language Server

NLS is a language server for the nickel programming language. NLS offer error messages, type hints, and auto-completion right in your favorite LSP-enabled editor.

Server

To be editor independent nls is made up of two components the server and possible lsp-client configurations that talk to the server directly. Hence, the server has to be installed separately to the client configuration.

Installation

The easiest way to install nls is using nix. nls is installed in the same installation as nickel:

To enter a shell with nickel and nls run

nix shell github:tweag/nickel

Client

VS Code

NLS is currently not available through the vscode marketplace. In the meantime, it can be built using Nix.

Either using the command line

code --install-extension $(nix build ./\#vscodeExtension --no-link --json | jq ".[0].outputs.vsix")

or in two steps, by first building the extension

nix build github:tweag/nickel#vscodeExtension.vsix

then installing it using Extension: Install from VSIX in the vscode command palette and choosing ./result-vsix/nls-client.vsix.

Configuration

The VS Code extension offers three configuration options:

• "nls.server.path": Path to nickel language server
• "nls.server.trace": "Enables performance tracing to the given file"
• "nls.server.debugLog": "Logs the communication between VS Code and the language server."