OpenEuphoria

Re: Parsing a Dice Roll String

• Posted by cklester <cklester at yahoo.com> Aug 05, 2004
• 448 views

Christian Cuvier wrote:
> > Subject: Parsing a Dice Roll String
> > posted by: cklester <cklester at yahoo.com>
> > I'm writing a die roller and need to be
> > able to parse a dice function string.
> > Some examples:
> >    3d6+5 (roll 6-sided die 3 times, add 5 to sum)
> >    4d6-Lowest (roll 6-sided die 4 times, discard lowest die)
> >    4d6-Highest (roll 6-sided die 4 times, discard highest die)
> >    2d10*3-3d4 (roll 10-sided die twice, multiply by 3, then subtract
> >                the result of rolling a 4-sided die three times)
> >    5d12/10 (roll 12-sided die five times, divide result by 10)
> > 
> > The current roller and a die-roll graphing program
> > can be found here: <a
> > href="http://www.cklester.com/euphoria/">http://www.cklester.com/euphoria/</a>
> 
> Well, I'd expect Matt's matheval.e to be able to handle this with minor text 
> translation.
> My understanding of your pb is: parse a string like roll ::=
> ({<number>d<sides>[<operation>(roll | <reference> |
> <constant>])[<operation>])+
> 
> where <reference is any of "Lowest" or "Highest" (any more?).
> What's to be stored in list_Rolls? The roll outcome?

Yes, along with the dice forumla.

3 d6
17 3d6
etc...

> <number> and <sides> are positive integers, <constant> is an atom..
> <operation> is any of +-*/ (any more?)
> Did I get it?

I think so! Now, where's the code for it, Parisian? :D

I think simplified, it can be written like:

(<number>d<sides>)+(<number>d<sides>|<constant>)...

Where + is any operator and <constant> is "Highest," "Lowest,"
an actual number, or whatever other value I can come up with to
modify the roll.

-=ck
"Programming in a state of EUPHORIA."
http://www.cklester.com/euphoria/