MM2 Language Support

Official Language Support, Syntax Highlighter, S-Expression Formatter, IntelliSense, Snippets, Hover Documentation, File Icons, and Execution Runner for Minimal Meta 2 (MM2) and MORK.

⚡ Quick Start for formatter: How to Enable "Format on Save"

To have your MM2 files automatically indented and formatted every time you save (Ctrl + S / Cmd + S), follow either method below:

Method 1: Via VS Code Settings UI

1. Press Ctrl + , (Linux/Windows) or Cmd + , (macOS).
2. Search for Format On Save check the box for Editor: Format On Save.
3. Search for Default Formatter select MM2 Language Support (mm2.mm2-syntax).

Method 2: Automatic Workspace Setup

Create or open the .vscode/settings.json file in your project root and paste:

{
  "editor.formatOnSave": true,
  "[mm2]": {
    "editor.defaultFormatter": "mm2.mm2-syntax",
    "editor.formatOnSave": true
  }
}

Method 3: Format Manually Anytime

• Shortcut: Press Shift + Alt + F (Linux/Windows) or Shift + Option + F (macOS).
• Command Palette: Press Ctrl + Shift + P $\to$ type Format Document.

🚀 Overview of Features

  ┌─────────────────────────────────────────────────────────────────────────┐
  │   🎨 Syntax Highlighter                                                 │
  │    Color hierarchy for Directives, Facts, Functions, Metavars, Staging  │
  ├─────────────────────────────────────────────────────────────────────────┤
  │   📁 Modern M² File Icon Theme                                          │
  │    Transparent vector M² glyphs for .mm2 and .mork in dark/light themes │
  ├─────────────────────────────────────────────────────────────────────────┤
  │   ✨ S-Expression Formatter                                             │
  │    Shift+Alt+F, Format on Save, multi-bracket pairing, comment spacing  │
  ├─────────────────────────────────────────────────────────────────────────┤
  │   💡 IntelliSense & 58+ Snippets                                        │
  │    Auto-complete + pure+<function> tab-expanding templates               │
  ├─────────────────────────────────────────────────────────────────────────┤
  │   🔍 Hover Tooltips                                                     │
  │    Live type signatures, descriptions & examples on mouse hover         │
  ├─────────────────────────────────────────────────────────────────────────┤
  │   ▶️ Cross-Platform File Runner                                         │
  │    Ctrl+F5, top-right Play icon, auto-save & auto-clear terminal        │
  └─────────────────────────────────────────────────────────────────────────┘

💡 IntelliSense & Code Snippets

Auto-Completion

Provides instant suggestions for built-in keywords, Rust primitives, pure functional templates, and math helpers. Triggered automatically as you type (, $, _, +, or letters.

Tab-Completable Snippets

Type any of the following prefixes and press Tab to expand:

1. def + Tab — Rule Definition

(DEF rule_name
    (, pattern)
    (O
        (+ (result))
    )
)

2. exec + Tab — Priority Execution Rule

(exec (0 0)
    (, pattern)
    (O
        (+ (fact))
    )
)

3. pure + Tab — Pure Evaluation

(pure (tag $out) $out
    (func (' $input))
)

4. pure+<function> + Tab — All Standard Library Function Snippets

Type pure+ or pure+<func> (e.g. pure+ge, pure+cons, pure+append) to instantly get fully-formed evaluation templates with appropriate quoting (' ...) and tab stops:

• Comparisons (pure+ge_i32, pure+gt_i32, pure+le_i32, pure+lt_i32, pure+eq_i32, pure+ne_i32):

  (pure (tag $out) $out
      (ge_i32 (i32_from_string arg1) (i32_from_string arg2))
  )
  

• Constructors & Substitution (pure+cons, pure+append, pure+substitute):

  (pure (tag $out) $out
      (cons (' ($head $tail)))
  )
  

  (pure (tag $out) $out
      (substitute (' ($pattern ($values))))
  )
  

• List Transforms (pure+reverse, pure+unique-atom, pure+sort-atom, pure+length):

  (pure (tag $out) $out
      (reverse (' $list))
  )
  

• Pattern Mining Primitives (pure+vars_to_indices, pure+indices_to_vars, pure+freshen-pattern, pure+partitions):

  (pure (tag $out) $out
      (indices_to_vars (' $list))
  )
  

• Boolean Logic (pure+and_bool, pure+or_bool, pure+xor_bool, pure+not_bool):

  (pure (tag $out) $out
      (and_bool bool1 bool2)
  )
  

🔍 Hover Tooltips

Hovering your mouse over any of the standard library helper functions displays an instant Markdown popup with its type signature, description, parameter breakdown, and usage examples:

• List Primitives
• Testing & Comparisons
• Relational Comparisons
• Boolean Logic
• Pattern Mining Helpers

▶️ Cross-Platform File Runner

Run any .mm2 file directly inside the integrated VS Code terminal with zero configuration.

• Play Button (▶): Located in the top-right editor title bar.
• Keyboard Shortcut: Ctrl + F5 (Linux/Windows) or Cmd + F5 (macOS).
• Context Menu: Right-click anywhere in the editor $\to$ MM2: Run File in Terminal.
• Auto-Save: Saves unpersisted changes automatically before terminal execution.
• Auto-Clear Terminal: Clears previous outputs before each run so you always see fresh results.
• Cross-Platform OS Support:
  • 🐧 Linux: Executes mork run "<file>" in Bash / Zsh / Fish.
  • 🍏 macOS: Executes mork run "<file>" in Zsh / Bash.
  • 🪟 Windows: Executes mork.exe run "<file>" in PowerShell / CMD / Git Bash / WSL.

⚙️ Extension Settings

Configure the extension by opening Settings (Ctrl + ,) searching for MM2:

Recommended Workspace Settings (.vscode/settings.json):

{
  "editor.formatOnSave": true,
  "[mm2]": {
    "editor.defaultFormatter": "mm2.mm2-syntax",
    "editor.formatOnSave": true
  },
  "mm2.runnerCommand": "mork run \"${file}\"",
  "mm2.clearTerminalBeforeRun": true
}

⌨️ Keyboard Shortcuts Reference

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