Need help debugging my programming...

ID:148210
 
May 25 2003, 9:01 pm
Ok, I'm working on a new racing game, and my problem is this...when I am in 5th gear and I try to down shift, it gets a runtime error, this one:

runtime error: list index out of bounds
proc name: Shift Down (/mob/verb/Shift_Down)
  source file: main.dm,249
  usr: Goku72 (/mob)
  src: Goku72 (/mob)
  call stack:


That's the only gear having problems when I downshift. I have no idea why, here's my downshift code...

        Shift_Down()
            if(!usr.gear.len)
                return 0
            else
                if((usr.currentgear%usr.gear.len)-1)
                    usr.currentgear=(usr.currentgear%usr.gear.len)-1
                    usr<<"<b>You shift to [usr.gear[usr.currentgear]]</b>"
                    return usr.currentgear
                else
                    return 0
May 26 2003, 9:06 am
Goku72 wrote:
>       Shift_Down()
>           if(!usr.gear.len)
>               return 0
>           else
>               if((usr.currentgear%usr.gear.len)-1)
>                   usr.currentgear=(usr.currentgear%usr.gear.len)-1
>                   usr<<"<b>You shift to [usr.gear[usr.currentgear]]</b>"
>                   return usr.currentgear
>               else
>                   return 0
>


usr.currentgear must be getting set to a bad value...to figure out what is happening, put in some debugging checks on the value...if it's less than 1 or larger than currentgear.len, report what it is without trying to do the downshift. (The ASSERT() proc is helpful for this sort of thing.)
May 28 2003, 1:04 am
In response to Deadron
I tried using ASSERT(), but I wasn't quite sure how to use it. I looked it up in the reference, it didn't express how to use it. Just told me to give it an argument.

This is how my list is defined:

list
                currentgear[0]
                gear[0]


And this is how I add the gears and such to it:
proc
            AddGears()
                src.gear=new
                src.gear.Add("R")
                src.gear.Add("N")
                var/gearmax=1
                while(src.highestgear>=gearmax)
                    src.gear.Add(num2text(gearmax))
                    gearmax++
                if((src.currentgear%src.gear.len)>2)
                    src.currentgear=(src.currentgear%src.gear.len)-1
                else
                    src.currentgear=(src.currentgear%src.gear.len)+2
May 28 2003, 12:52 pm
In response to Goku72
ASSERT() is exactly like an if() statement, but it causes the proc to crash with an error message if it's false.