Source code for evennia.contrib.rpg.dice.dice

"""
# Dice

Rolls dice for roleplaying, in-game gambling or GM:ing

Evennia contribution - Griatch 2012

This module implements a a dice-roller and a `dice`/`roll` command
to go with it. It uses standard RPG 'd'-syntax (e.g. 2d6 to roll two
six-sided die) and also supports modifiers such as 3d6 + 5.

    > roll 1d20 + 2

One can also specify a standard Python operator in order to specify
eventual target numbers and get results in a fair and guaranteed
unbiased way.  For example a GM could (using the dice command) from
the start define the roll as 2d6 < 8 to show that a roll below 8 is
required to succeed. The command will normally echo this result to all
parties (although it also has options for hidden and secret rolls).


# Installation:


Add the `CmdDice` command from this module to your character's cmdset
(and then restart the server):

```python
# in mygame/commands/default_cmdsets.py

# ...
from evennia.contrib.rpg import dice  <---

class CharacterCmdSet(default_cmds.CharacterCmdSet):
    # ...
    def at_cmdset_creation(self):
        # ...
        self.add(dice.CmdDice())  # <---

```

# Usage:

    roll 1d100 + 10

To roll dice in code, use the `roll` function from this module:

    from evennia.contrib.rpg import dice

    dice.roll("3d10 + 2")


If your system generates the dice dynamically you can also enter each part
of the roll separately:

    dice.roll(3, 10, ("+", 2))  # 3d10 + 2


"""

import re
from ast import literal_eval
from random import randint

from evennia import CmdSet, default_cmds
from evennia.utils.utils import simple_eval


[docs]def roll( dice, dicetype=6, modifier=None, conditional=None, return_tuple=False, max_dicenum=10, max_dicetype=1000, ): """ This is a standard dice roller. Args: dice (int or str): If an `int`, this is the number of dice to roll, and `dicetype` is used to determine the type. If a `str`, it should be on the form `NdM` where `N` is the number of dice and `M` is the number of sides on each die. Also `NdM [modifier] [number] [conditional]` is understood, e.g. `1d6 + 3` or `2d10 / 2 > 10`. dicetype (int, optional): Number of sides of the dice to be rolled. Ignored if `dice` is a string. modifier (tuple, optional): A tuple `(operator, value)`, where operator is one of `"+"`, `"-"`, `"/"` or `"*"`. The result of the dice roll(s) will be modified by this value. Ignored if `dice` is a string. conditional (tuple, optional): A tuple `(conditional, value)`, where conditional is one of `"=="`,`"<"`,`">"`,`">="`,`"<=`" or "`!=`". Ignored if `dice` is a string. return_tuple (bool): Return a tuple with all individual roll results or not. max_dicenum (int): The max number of dice to allow to be rolled. max_dicetype (int): The max number of sides on the dice to roll. Returns: int, bool or tuple : By default, this is the result of the roll + modifiers. If `conditional` is given, or `dice` is a string defining a conditional, then a True/False value is returned. Finally, if `return_tuple` is set, this is a tuple `(result, outcome, diff, rolls)`, where, `result` is the the normal result of the roll + modifiers, `outcome` and `diff` are the boolean absolute difference between the roll and the `conditional` input; both will be will be `None` if `conditional` is not set. The `rolls` a tuple holding all the individual rolls (one or more depending on how many dice were rolled). Raises: TypeError if non-supported modifiers or conditionals are given. Notes: All input numbers are converted to integers. Examples: :: # string form print roll("3d6 + 2") 10 print roll("2d10 + 2 > 10") True print roll("2d20 - 2 >= 10") (8, False, 2, (4, 6)) # roll was 4 + 6 - 2 = 8 # explicit arguments print roll(2, 6) # 2d6 7 print roll(1, 100, ('+', 5) # 1d100 + 5 4 print roll(1, 20, conditional=('<', 10) # let'say we roll 3 True print roll(3, 10, return_tuple=True) (11, None, None, (2, 5, 4)) print roll(2, 20, ('-', 2), conditional=('>=', 10), return_tuple=True) (8, False, 2, (4, 6)) # roll was 4 + 6 - 2 = 8 """ modifier_string = "" conditional_string = "" conditional_value = None if isinstance(dice, str) and "d" in dice.lower(): # A string is given, parse it as NdM dice notation roll_string = dice.lower() # split to get the NdM syntax dicenum, rest = roll_string.split("d", 1) # parse packwards right-to-left if any(True for cond in ("==", "<", ">", "!=", "<=", ">=") if cond in rest): # split out any conditionals, like '< 12' rest, *conditionals = re.split(r"(==|<=|>=|<|>|!=)", rest, maxsplit=1) try: conditional_value = int(conditionals[1]) except ValueError: raise TypeError( f"Conditional '{conditionals[-1]}' was not recognized. Must be a number." ) conditional_string = "".join(conditionals) if any(True for op in ("+", "-", "*", "/") if op in rest): # split out any modifiers, like '+ 2' rest, *modifiers = re.split(r"(\+|-|/|\*)", rest, maxsplit=1) modifier_string = "".join(modifiers) # whatever is left is the dice type dicetype = rest else: # an integer is given - explicit modifiers and conditionals as part of kwargs dicenum = int(dice) dicetype = int(dicetype) if modifier: modifier_string = "".join(str(part) for part in modifier) if conditional: conditional_value = int(conditional[1]) conditional_string = "".join(str(part) for part in conditional) try: dicenum = int(dicenum) dicetype = int(dicetype) except Exception: raise TypeError( f"The number of dice and dice-size must both be numerical. Got '{dicenum}' " f"and '{dicetype}'." ) if 0 < dicenum > max_dicenum: raise TypeError(f"Invalid number of dice rolled (must be between 1 and {max_dicenum}).") if 0 < dicetype > max_dicetype: raise TypeError(f"Invalid die-size used (must be between 1 and {max_dicetype} sides).") # roll all dice, remembering each roll rolls = tuple([randint(1, dicetype) for _ in range(dicenum)]) result = sum(rolls) if modifier_string: result = simple_eval(f"{result} {modifier_string}") outcome, diff = None, None if conditional_string and conditional_value: outcome = simple_eval(f"{result} {conditional_string}") diff = abs(result - conditional_value) if return_tuple: return result, outcome, diff, rolls elif conditional or (conditional_string and conditional_value): return outcome # True|False else: return result # integer
# legacy alias roll_dice = roll RE_PARTS = re.compile(r"(d|\+|-|/|\*|<|>|<=|>=|!=|==)") RE_MOD = re.compile(r"(\+|-|/|\*)") RE_COND = re.compile(r"(<|>|<=|>=|!=|==)")
[docs]class CmdDice(default_cmds.MuxCommand): """ roll dice Usage: dice[/switch] <nr>d<sides> [modifier] [success condition] Switch: hidden - tell the room the roll is being done, but don't show the result secret - don't inform the room about neither roll nor result Examples: dice 3d6 + 4 dice 1d100 - 2 < 50 This will roll the given number of dice with given sides and modifiers. So e.g. 2d6 + 3 means to 'roll a 6-sided die 2 times and add the result, then add 3 to the total'. Accepted modifiers are +, -, * and /. A success condition is given as normal Python conditionals (<,>,<=,>=,==,!=). So e.g. 2d6 + 3 > 10 means that the roll will succeed only if the final result is above 8. If a success condition is given, the outcome (pass/fail) will be echoed along with how much it succeeded/failed with. The hidden/secret switches will hide all or parts of the roll from everyone but the person rolling. """ key = "dice" aliases = ["roll", "@dice"] locks = "cmd:all()"
[docs] def func(self): """Mostly parsing for calling the dice roller function""" if not self.args: self.caller.msg("Usage: @dice <nr>d<sides> [modifier] [conditional]") return argstring = "".join(str(arg) for arg in self.args) parts = [part for part in RE_PARTS.split(self.args) if part] len_parts = len(parts) modifier = None conditional = None if len_parts < 3 or parts[1] != "d": self.caller.msg( "You must specify the die roll(s) as <nr>d<sides>." " For example, 2d6 means rolling a 6-sided die 2 times." ) return # Limit the number of dice and sides a character can roll to prevent server slow down and crashes ndicelimit = 10000 # Maximum number of dice nsidelimit = 10000 # Maximum number of sides if int(parts[0]) > ndicelimit or int(parts[2]) > nsidelimit: self.caller.msg("The maximum roll allowed is %sd%s." % (ndicelimit, nsidelimit)) return ndice, nsides = parts[0], parts[2] if len_parts == 3: # just something like 1d6 pass elif len_parts == 5: # either e.g. 1d6 + 3 or something like 1d6 > 3 if parts[3] in ("+", "-", "*", "/"): modifier = (parts[3], parts[4]) else: # assume it is a conditional conditional = (parts[3], parts[4]) elif len_parts == 7: # the whole sequence, e.g. 1d6 + 3 > 5 modifier = (parts[3], parts[4]) conditional = (parts[5], parts[6]) else: # error self.caller.msg("You must specify a valid die roll") return # do the roll try: result, outcome, diff, rolls = roll_dice( ndice, nsides, modifier=modifier, conditional=conditional, return_tuple=True ) except ValueError: self.caller.msg( "You need to enter valid integer numbers, modifiers and operators." " |w%s|n was not understood." % self.args ) return # format output if len(rolls) > 1: rolls = ", ".join(str(roll) for roll in rolls[:-1]) + " and " + str(rolls[-1]) else: rolls = rolls[0] if outcome is None: outcomestring = "" elif outcome: outcomestring = " This is a |gsuccess|n (by %s)." % diff else: outcomestring = " This is a |rfailure|n (by %s)." % diff yourollstring = "You roll %s%s." roomrollstring = "%s rolls %s%s." resultstring = " Roll(s): %s. Total result is |w%s|n." if "secret" in self.switches: # don't echo to the room at all string = yourollstring % (argstring, " (secret, not echoed)") string += "\n" + resultstring % (rolls, result) string += outcomestring + " (not echoed)" self.caller.msg(string) elif "hidden" in self.switches: # announce the roll to the room, result only to caller string = yourollstring % (argstring, " (hidden)") self.caller.msg(string) string = roomrollstring % (self.caller.key, argstring, " (hidden)") self.caller.location.msg_contents(string, exclude=self.caller) # handle result string = resultstring % (rolls, result) string += outcomestring + " (not echoed)" self.caller.msg(string) else: # normal roll string = yourollstring % (argstring, "") self.caller.msg(string) string = roomrollstring % (self.caller.key, argstring, "") self.caller.location.msg_contents(string, exclude=self.caller) string = resultstring % (rolls, result) string += outcomestring self.caller.location.msg_contents(string)
[docs]class DiceCmdSet(CmdSet): """ a small cmdset for testing purposes. Add with @py self.cmdset.add("contrib.dice.DiceCmdSet") """
[docs] def at_cmdset_creation(self): """Called when set is created""" self.add(CmdDice())