Adding lists to a list

ID:136069
 
Jul 27 2003, 5:26 pm
This is the way I *think* that BYOND works, I don't feel like taking a break from working on my game (motivation is that scarce) to make sure that I am correct.

If you have a list, and you add a list to it, then it makes it one list.
var/list/somelist = new/list() somelist += list(1,2,3) somelist += list(4,5,6)
That should result in somelist being a list with six elements: 1,2,3,4,5 and 6. However, what if you wanted a list of lists. The way it works, somelist[1] equals 1, what if you wanted somelist[1] to be list(1,2,3)?

I ran into this situation, but I found a workaround that probably works better than using a list of lists like I had originally thought to do.
Jul 27 2003, 6:14 pm
If I remember right, if you want to add a list L to another list X (and have L retained as a list instead of its items becoming items of X) you can do it with X += list(L). Sounds like you thought of that already, though.
Jul 27 2003, 6:31 pm
In response to Gughunter
Actually, I didn't. I figured that using datums would work even better. Anyway, I finished the routine that all of that was part of, otherwise I'd consider going back and trying that. Thanks though, I'll keep this in mind.
Jul 29 2003, 1:03 pm
In response to OneFishDown
You can also do something along the lines of "list[1][1]" to output the first thing on the first list in the list itself, comes in handy if you're trying to access items within a list that is within a list itself.
Jul 29 2003, 1:49 pm
In response to Gughunter
Gughunter wrote:
If I remember right, if you want to add a list L to another list X (and have L retained as a list instead of its items becoming items of X) you can do it with X += list(L). Sounds like you thought of that already, though.

That shouldn't work; whenever you add a list to another list, BYOND will assume you want to add the items in it. This is how you'd do it:
var/i = mylist.len
mylist += null
mylist[++i] = list(1,2,3)
The trick is, you can get a list of lists by setting a value directly.

You can also use association to do that.
mylist[list(1,2,3)] = null

Lummox JR
Jul 29 2003, 2:17 pm
In response to Lummox JR
The method Gughunter mentioned does in fact work. Following the + operator the contents of the list will be added to the list, but the contents of the list is a list so the intact list will be appended.
Jul 29 2003, 4:37 pm
In response to tenkuu
tenkuu wrote:
The method Gughunter mentioned does in fact work. Following the + operator the contents of the list will be added to the list, but the contents of the list is a list so the intact list will be appended.

Ah. I hadn't realized what he was doing exactly. But you're right.

Lummox JR