Dice::DSL

Dice::DSL was an attempt to build a dice parser that I could use for random games. The alternate goal was to define a library in a language I was somewhat familiar with (Ruby) and then folllow up with a project in a language I wasn't familiar with (Rust using the Helix bindings). I never got around to using Helix, but this library now includes both the ruby and, three years later, a rust version.

Installation

Add this line to your application's Gemfile:

gem 'dice-dsl'

And then execute:

$ bundle

Or install it yourself as:

$ gem install dice-dsl

Usage

This is a dice roller with options for more complex rules. For each roll type, a vector of the values rolled or a scalar value which is the sum can be returned.

Dice::SimpleRoll.parse('4d6') allows for a roll of any number of dice
Dice::ModifiedRoll.parse('3d6+3') allows for a roll of any number of dice modified by a fixed amount
Dice::ModifyEachRoll.parse('3d6++2') allows for a roll of any number of dice where each is modified by a fixed amount
Dice::ExplodingRoll.parse('2d6!') allows for a roll of dice; if all the dice rolled are the maximum value then the die is rerolled. This continues until a non-maximum die is rolled
Dice::ExplodeEachRoll.parse('3d6!!') allows for a roll of dice; for each die that is the maximum value reroll until a non maximum value is rolled
Dice::TakeN.parse('4d6^3') or Dice::TakeN.parse('4d6`3') or Dice::TakeN.parse('4d6~3') take the top, bottom or middle N of a series of rolled dice
Dice::RollList.parse('3d6, 2d8--1, 1d10, 2d12++1') builds a vector of all the individial dice rolls separated by commas

There is a histogram class that can generate a chart of the given results:

h = Dice::Histogram.new('2d8!!')
puts h.linear_chart

2   **
3   *****
4   *********
5   ***********
6   **************
7   *****************
8   ********************
9   ******************
10  ***************
11  ************
12  ***********
13  ********
14  ******
15  ****
16  *****
17  ****
18  ****
19  ***
20  **
21  *
22  *
23  
24  *
25  *

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Development (2)

There is also a top-level Cargo.toml and src directory to define a rust based library and command line application. It works similarly to the ruby version:

> cargo build --release
> target/release/roll --chart 2d8\!\!
 2. 100.0: ********
 3.  98.4: ***************
 4.  95.2: ***********************
 5.  90.3: ******************************
 6.  84.0: *************************************
 7.  76.3: ********************************************
 8.  66.9: ***************************************************
 9.  56.1: ********************************************
10.  46.8: ***************************************
11.  38.6: *********************************
12.  31.6: ****************************
13.  25.7: **********************
14.  21.1: *****************
15.  17.6: ***********
16.  15.3: *************
17.  12.6: ***********
18.  10.2: **********
19.   8.1: ********
20.   6.5: *******
21.   5.1: ******
22.   3.9: ****
23.   3.2: ***
24.   2.8: ***
25.   2.2: **
26.   1.8: **
27.   1.4: **
28.   1.1: **
29.   0.8: *
30.   0.7: *
31.   0.5: *
32.   0.5: *
33.   0.4: *
34.   0.3: *
35.   0.2: *
36.   0.2: *
37.   0.1: *
38.   0.1: *
39.   0.1: *
40.   0.1: *
41.   0.1: *
42.   0.0: *

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/palmergs/dice-dsl.

License

The gem is available as open source under the terms of the MIT License.