A library for evaluating tabletop dice roll expressions.
Used in the Mastodon bot DiceCat, and the IRC bot DesertBot
Sample usage:
5d6!>4 + (5d(2d10)dl - d10) * (d20 / 2) # for an unnecessarily complicated roll
Sample output:
84 for an unnecessarily complicated roll
There is also a verbose mode that outputs every individual die roll, that output looks like this:
[2d10: 2,5 (7) | 5d7: -1-,6,2,4,5 (17) | 1d10: 3 (3) | 1d20: 9 (9) | 5d6: 2,2,3,*5*,*5*,2,*5*,4 (28)] 84 for an unnecessarily complicated roll
- Arithmetic:
+-*/%^()(addition, subtraction, multiplication, division, modulus, exponent, parentheses) - Dice:
#d#(eg,3d6,d20)- Rolls the left number of dice with the right number of sides.
3d6rolls 3 six-sided dice - The first number is optional and defaults to 1 if omitted
- Rolls the left number of dice with the right number of sides.
- Dice modifiers:
- Keep/Drop Highest/Lowest:
kh#kl#dh#dl#- Keeps/Drops only the # highest/lowest dice rolls. Any that are either not kept or dropped are removed from the total
- The number is optional and defaults to 1 if omitted
- Exploding:
!!#!>#!>=#!<#!<=#- Each die that rolls maximum (
!), or a specific number (!#), or over/under a threshold (!>#!>=#!<#!<=#), adds an additional die to the pool- This repeats for each die added to the pool
- Each die that rolls maximum (
- Reroll:
rr#r>#r>=#r<#r<=#- Drops and rerolls each die that rolls minimum (
r), or a specific number (r#), or over/under a threshold (r>#r>=#r<#r<=#)- This repeats for each die rerolled. You can make it only reroll each die once with
roinstead ofr
- This repeats for each die rerolled. You can make it only reroll each die once with
- Drops and rerolls each die that rolls minimum (
- Count:
cc#c>#c>=#c<#c<=#- Counts the number of dice that roll maximum (
c), or a specific number (c#), or over/under a threshold (c>#c>=#c<#c<=#)
- Counts the number of dice that roll maximum (
- Sorting:
ssasd- Sorts the dice rolls in ascending (
ssa) or descending (sd) order - This still applies in non-verbose mode but you won't see any visible effect
- Sorts the dice rolls in ascending (
- Keep/Drop Highest/Lowest:
- Comments:
# your comment here- Adds a comment to the end of the output, so you can describe what the roll is for. eg:
d20+5 # for initiative - The
#is a literal hash, not a number this time :)
- Adds a comment to the end of the output, so you can describe what the roll is for. eg:
If you have more ideas for operators, suggestions and pull requests are welcome!