Difference between revisions of "LlDeleteSubList"

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m (broke the example (why was it even changed?))
(history tracks authorship, signing isn't necessary or beneficial for examples)
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|return_text=that is the '''src''' list with the slice from '''start''' to '''end''' removed.
|return_text=that is the '''src''' list with the slice from '''start''' to '''end''' removed.
|spec
|spec
|caveats
|caveats=* '''src''' is not modified, remember to use or store the result or this function.
|constants
|constants
|examples=
|examples=<lsl>default
<lsl>
/////////////////////////////
// Author: Bird Raven
// For Use As OpenSource
/////////////////////////////
default
{
{
     state_entry()
     state_entry()
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         // list names = ["Edgar"];
         // list names = ["Edgar"];
     }
     }
}
}</lsl>
</lsl>
|helpers
|helpers
|also_functions
|also_functions

Revision as of 14:41, 24 May 2008

Summary

Function: list llDeleteSubList( list src, integer start, integer end );
0.0 Forced Delay
10.0 Energy

Returns a list that is the src list with the slice from start to end removed.

• list src
• integer start start index
• integer end end index

start & end support negative indexes.

Specification

Index Positive Negative
First 0 -length
Last length - 1 -1

Indexes

  • Positive indexes count from the beginning, the first item being indexed as 0, the last as (length - 1).
  • Negative indexes count from the far end, the first item being indexed as -length, the last as -1.

Caveats

  • If either start or end are out of bounds the script continues to execute without an error message.
  • start & end will form an exclusion range when start is past end (Approximately: start > end).
  • src is not modified, remember to use or store the result or this function.

Examples

<lsl>default {

   state_entry()
   {
       // Create a list of names
       list names = ["Anthony", "Bob", "Charlie", "Dan", "Edgar", "Gerald"];
       
       // Now let's remove values at position 1 through 2.
       names = llDeleteSubList(names, 1, 2);
       // Result:
       // list names = ["Anthony", "Dan", "Edgar", "Gerald"];
       
       // Now let's use an start number higher then our end number
       names = llDeleteSubList(names, 3, 1);
       
       // Result:
       // list names = ["Edgar"];
   }
}</lsl>

Notes

Ranges & Indexes

The easiest way to explain how ranges work is to make all indexes positive. Negative indexes are just a way of counting from the tail end instead of the beginning, all negative indexes have a corresponding equivalent positive index (assuming they are in range). Positive indexes past length (after the last index), or negative indexes past the beginning (before the first index) are valid and the effects are predictable and reliable: the entries are treated as if they were there but were removed just before output.

  • If start <= end then the range operated on starts at start and ends at end. [start, end]
  • Exclusion range: If start > end then the range operated on starts at 0 and goes to end and then starts again at start and goes to -1. [0, end] + [start, -1]
    • If end is a negative index past the beginning, then the operating range would be [start, -1].
    • If end is a positive index past the end, then the operating range would be [0, end].
    • If both start and end are out of bounds then the function would have no operating range (effectively inverting what the function is supposed to do).

See negative indexes for more information.

See Also

Articles

•  Negative Index

Deep Notes

Signature

function list llDeleteSubList( list src, integer start, integer end );