🎲 reroll

A powerful and flexible command-line dice roller for tabletop games and probability testing.

Supports:

• Standard dice expressions like d8,3d6, 4d6kh3, and 2d10dl1
• Arithmetic operations: +, -, *, /
• Repetition syntax: 3(1d6+2) rolls 1d6+2 three times
• Modifiers: explode (!), keep/drop high/low (k/kh, kl, d/dh, dl)

🧾 Usage

reroll "4d6kh3 + 2"
reroll "3(2d8+1)"
reroll "1d20 + 5" 

Use quotes around expressions to avoid shell interference.

🔍 Options

• -v or --verbose: Show all final rolls.
• -h or --help: Print help and usage info.

✨ Features

• Full support for nested expressions with correct order of operations
• Exploding dice (e.g., 1d6!) with custom thresholds (e.g., 1d6!5)
• Deterministic expression parsing using pest

🧪 Example Output

$ reroll "4d6kh3"
14

$ reroll -v "4d6kh3"
[6, 4, 4]

🔧 Install

cargo install reroll

📁 File Structure

• src/parser.rs: Expression parsing (via Pest)
• src/eval.rs: Expression evaluation and dice logic
• src/main.rs: CLI frontend

📜 Syntax Reference

Example	Meaning
3d6	Roll 3 six-sided dice
4d6kh3	Roll 4d6, keep the highest 3
2d8dl1	Roll 2d8, drop the lowest 1
1d6!	Exploding dice on max roll
3(1d6+2)	Roll 1d6+2 three times
(2d6+1)*2	Roll and apply arithmetic

---

Made with 🍀 for dice goblins and probability nerds.