Manipulating lists through a function

[Nova Convair]

Multiple possible solutions.

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Strided lists will of course help here to manage multiple lists in one.

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Another way is to add markers to the list. Example:
list data = ["@1","1","2","3","@2","3","4","5","@3", ..... ,"@21"];

You call your function with parameter index=2 for example and do:
integer start = llListFindList(data,["@"+(string)index]) + 1;
integer end = llListFindList(data,["@"+(string)(index+1)]) - 1;

you find your list elements from start to end in the data list

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Another way is to store separated strings in lists. Example:
list data = ["1|2|3","4|5|6","7|8|9" .... ];

You call your function with parameter index=2 for example and do:
list sublist = llParseStringKeepNulls(llList2List(data,index,index),["|"],[]);

your list elements are in sublist

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If the sublists have all the same length a simple calculation gives you the index of the sublist

 

The best solution depends on the circumstances and details of your application

Edited July 29, 2018 by Nova Convair