Lambda Black

Lambda Black is a VS Code color theme optimised for Haskell with extra syntax colors for more language scopes. It's based on Groovy Lambda but is very ungrooved and doesn't break languages other than Haskell, but actually improves them.

Color schemes

Black:

Dark+:

Features

Lambda Black supports all TextMate scopes provided by the Language Haskell VS Code extension, making it able to:

• disambiguate between data constructors and types in data declarations,
• distinguish qualified names from other identifiers,
• distinguish different uses of @: type application, record syntax or infix operator,
• special highlighting for record fields,
• highlights MagicHash and OverloadedLabels,

Installation

You can get Lambda Black on:

• Visual Studio Marketplace
• Open-VSX Registry

Or install it from source:

1. Install dependencies:

   • git
   • npm, or pnpm or yarn
   • and only on Linux, libsecret

2. Clone the repo, build and install the extension:

   git clone --depth 1 git@github.com:janw4ld/lambda-black.git && {
     cd lambda-black
     
     npm install --save-dev @vscode/vsce
     npm exec vsce package
   
     code --install-extension lambda-black-*.vsix
   }

Alternatively, you can clone this repo into your VS Code extensions directory (usually $HOME/.vscode/extensions/), then restart VS Code. Seems broken as of 1.76.1.

Customisation

To change how something is highlighted, proceed as follows:

• While browsing code containing highlighting you'd like to change, start the TextMate scope inspector as follows:
  • open the VS Code Command Palette (Ctrl+Shift+P),
  • start typing "Inspect Editor Tokens and Scopes" and select this item from the dropdown menu.
• Click on the code whose highlighting you'd like to change; this will display the TextMate scopes associated to that piece of code. For instance, if in a Haskell source file is given the scope keyword.control.if.haskell.
• Open your settings.json file:
  • open the VS Code Command Palette (Ctrl+Shift+P),
  • start typing "Open Settings (JSON)" and select this item from the dropdown menu.
• Make the modifications by editing the value of editor.tokenColorCustomizations in your settings. For instance, to highlight if and then in red and else in blue, one would write:

    "editor.tokenColorCustomizations": {
      "textMateRules": [
        {
          "scope": [ "keyword.control.if", "keyword.control.then" ],
          "settings": {
            "foreground": "#ff0000"
          }
        },
        {
          "scope": "keyword.control.else",
          "settings": {
            "foreground": "#0000ff"
          }
        }
      ]
    }