Editor Setup

WCL ships a language server (wcl lsp) that implements the Language Server Protocol. Any LSP-capable editor can use it. This page covers setup for VS Code, Neovim, and Helix.

LSP Features

• Real-time diagnostics (parse errors, type mismatches, schema violations)
• Hover documentation for blocks, attributes, and schema definitions
• Go-to-definition for block references and macro uses
• Completions for attribute names, block types, schema names, and decorator names
• Semantic token highlighting
• Signature help for macro and built-in function calls
• Find references
• Document formatting (wcl fmt integration)

VS Code

A bundled VS Code extension is located in editors/vscode/ in the repository. It handles syntax highlighting, LSP integration, and file association for .wcl files.

Install with just (if you have just installed):

just install-vscode

Install manually:

cd editors/vscode && npm install
ln -sfn "$(pwd)" ~/.vscode/extensions/wil.wcl-0.1.0

The symlink approach means changes to the extension source are picked up immediately without reinstalling. Restart VS Code (or run “Developer: Reload Window”) after linking.

The extension automatically starts wcl lsp when a .wcl file is opened. Make sure wcl is on your PATH (i.e., installed via cargo install --path crates/wcl).

Neovim

Add the following to your Neovim configuration (e.g., in an ftplugin/wcl.lua or your main init.lua):

vim.lsp.start({
    name = "wcl",
    cmd = { "wcl", "lsp" },
    root_dir = vim.fs.dirname(vim.fs.find({ ".git" }, { upward = true })[1]),
    filetypes = { "wcl" },
})

You will also want to register the .wcl filetype so Neovim recognizes it:

vim.filetype.add({
    extension = {
        wcl = "wcl",
    },
})

If you use nvim-lspconfig, a custom server entry works the same way — pass cmd = { "wcl", "lsp" } and set filetypes = { "wcl" }.

Helix

Add the following to your ~/.config/helix/languages.toml:

[[language]]
name = "wcl"
scope = "source.wcl"
file-types = ["wcl"]
language-servers = ["wcl-lsp"]

[language-server.wcl-lsp]
command = "wcl"
args = ["lsp"]

Helix will start wcl lsp automatically when a .wcl file is opened. Run hx --health wcl to verify the language server is detected correctly.

Other Editors

Any editor with LSP support can use the WCL language server. The server communicates over stdio and is started with:

wcl lsp

Refer to your editor’s LSP documentation for how to register a custom language server with that command.