Updating a variable in a list

[CampSoup1988]

Ok, lets say I want to track the donations of three people.  I have a variable called DonationTotal which stores [0,0,0]

I have tried a number of ways to update lets say the second number in the list, but I keep getting errors.

 

Oh, and Current has the integer 2.

 

These are the different methods I have tried and their errors:

llList2Integer(DonationTotal, Current) += amount;

 but I got: The left-hand side of an assignment must be a variable, property or indexer

 

DonationTotal[current] += amount;

 and got:

Expected ; or = (cannot specify constructor arguments in declaration)

; expected

Invalid expression term '+='

; expected

 

I also tried a few other similar combinations, which got me the same results of those previous two attempts.

 

If anyone has any advice, I would be greatly appreciated!

 

Thank you,

CampSoup1988

[Cerise Sorbet]

Hi, LSL llists look like they should behave as arrays from other languages, but they do not. We need to use helper functions.

We can't do DonationTotal[current] += amount;

but instead you might use --

DonationTotal = llListReplaceList(DonationTotal, [llList2Integer(DonationTotal, current) + amount], current, current);

The LSL List category page has more information and other options to juggle them.

[CampSoup1988]

So I have to replace the entire list....

 

I was kind of hoping to avoid that as in reality the list would be a lot longer then just three varaible.  Actually it is open ended depending on how many staffers are added to the list

 

And yes, I had previously dug deeply into that wiki.

[Cerise Sorbet]

---

CampSoup1988 wrote:

So I have to replace the entire list....

---

Yes. Sometimes we can lessen the memory pain if we chop the lists, do lots of work, then reassemble them at the end, but there is not too much flexibility.

[CampSoup1988]

As far as I know, I dont think my idea would even be possible then, since I dont have a fixed size for the list

 

and to be honest, I would naturally have done DonationTotal[current]+=ammount;

[Darkie Minotaur]

There are almost always ways to do stuff in lsl - mot of the fun you have when coding lsl is to find ways to make somthing work that dorn't work in the straight forward way.

[Helium Loon]

Knowing the list length isn't an issue, since it is available using llGetListLength(list).  The typical way of doing this is already laid out in the wiki as an example function from the LSL_List page, though you'd have to alter it to use an index instead of 'searching' the list for a match (which isn't hard.)

 

ListItemReplace function

 

If you want to have it do something other than strings, you can change the function parameters to utilize another type, or even generalize the function by extending it to take in an integer that is the return from a llGetListEntryType() call, and use that to convert the input 'newvalue' to the correct type.

 

[CampSoup1988]

I dont see how you could modify ListItemReplace to search by index instead of the content of the list

[Rolig Loon]

As written, the function uses llListFindList to create the variable placeinlist, but if you already know where the item you want to replace is, you don't have to look for it.  Just pass the function your known value of placeinlist and then use llListReplaceList to do the update.

[CampSoup1988]

Ahhh, I totally overlooked that!  Thank you

[Void Singer]

you can also limit lists to a specific length by adding and then only grabbing elements from the front or the back (depending on where you are adding and which ones are important.

[Miranda Umino]

This code below costs many creation of lists .. Let s cross fingers that the garbage collector works well

 

 

list ListReplaceIntegerElementByIndex(list l , integer index , integer value){    return llList2List(  l , 0, index -1 ) + (list)value +  llList2List( l ,  index +1 , -1 );}default{    state_entry()    {        // displays Object: 10, 20, 30, 40, 1000, 60, 70, 80, 90        llOwnerSay(llList2CSV( ListReplaceElementByIndex( [ 10, 20, 30, 40, 50, 60, 70, 80, 90 ], 4, 1000)));    }}

 

[Void Singer]

what wrong with

l = llListReplaceList( l, [value], index, index );

??

[Miranda Umino]

:matte-motes-big-grin-squint: void , my bad .. i was tired ...