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llSubStringIndex

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function
Function syntax
integer llSubStringIndex(
  1. string source,// Source string to search within.
  2. string pattern// Substring pattern to search for.
);
Returns
integer
Energy
10

If pattern is not found in source, -1 (in LSL) or nil (in SLua) is returned.

The index of the first character in the string is 0

Returns an integer that is the index of the first instance of pattern in source.

How to use
integer result = llSubStringIndex("", "");

Caveats

Section titled “Caveats”
  • Performs a literal match (case sensitive).
  • Wildcards and RegEx are not supported.
  • If pattern is an empty string the value returned is 0 rather than -1.
  • There is no function to search the string starting at a specific offset. check See Also for a function to search from the end.

Examples

Section titled “Examples”
Example 1
default
{
    touch_start(integer num_detected)
    {
        string  name       = llDetectedName(0);
        integer spaceIndex = llSubStringIndex(name, " ");


//      no conditional check is needed for (spaceIndex == -1)
8 collapsed lines
//      because we KNOW the legacy name must have a space


//      extract the substring from the first character to the one before the space
        string  firstName  = llGetSubString(name, 0, spaceIndex - 1);


        llSay(PUBLIC_CHANNEL, firstName + " touched me.");
    }
}
Example 2
19 collapsed lines
default
{
    state_entry()
    {
        llSensorRepeat("", NULL_KEY, AGENT_BY_LEGACY_NAME, PI, 96.0, 20);
    }


    sensor(integer num_detected)
    {
    //  Loop through all the sensor data and match against " Linden",
    //  this causes it to match with any last name of Linden (since there can't be spaces before the firstname)
    //  Alternatively you could match a firstname with "FirstName " or anything else


        integer index;
        do
        {
            key avatarKey = llDetectedKey(index);
            string avatarLegacyName = llDetectedName(index);


        //  watch out for the bitwise-NOT (~)
        //  the next line translates to if (indexOfSearchedStringInOtherString != -1)
            integer isReallyALinden = ~llSubStringIndex(avatarLegacyName, " Linden");


            if (isReallyALinden)
5 collapsed lines
                llInstantMessage(avatarKey, "Hello, I see you!");
        }
        while (++index < num_detected);
    }
}
Basic Example:
integer index = llSubStringIndex("string data","TEST");
if(index == -1) {
    llSay(PUBLIC_CHANNEL,"TEST was not found in the string");
} else {
    llSay(PUBLIC_CHANNEL,"TEST was found in the string.");
}
Example 4

String Cheese

Section titled “String Cheese”
34 collapsed lines
//This example shows how you can ask if a word or group of words is in a given string.
//There is a limitation with this function. Your search of the string is for an exact match (case sensitive)
//so the string_example below would be hard to match.


string string_example = "ThIs serVes As aN exaMplE sTrinG. It ISn't toO coMPleX bUt HaS sOme mIlD vARietY";


//If you chat a question "Search for search_word" within range of the object this script is in
//it will recognize (by searching the chat msg) the "search for" part and take the word or words following it
//and check the string_example for those words.


string search_test_a = "seArCh foR";


//The example below works the same way but searches for the word in front of the recognized trigger question.


string search_test_b = "is the word I seek";


//Using this variable provides a way to manipulate the word(s) during the script without damaging the msg.


string search_word;


// Provide a mnemonic for the -1 return code that means NOT FOUND
integer NOT_FOUND = -1;


default
{
    on_rez(integer param)//Although reseting the script on_rez provides many benefits
    { //in some cases it would be a bad idea because stored variables, lists and queued events would be trashed.
        llResetScript();
    }
    state_entry()
    {   //This is just for fun (but better to know what object is talking to you).
        llSetObjectName("String Cheese");
        llListen(PUBLIC_CHANNEL, "", llGetOwner(), "");//Listen to you on the public chat channel for everything you say.
    }
    listen(integer chan, string name, key id, string msg)
    {
        if(llSubStringIndex(llToUpper(msg), llToUpper(search_test_a)) != NOT_FOUND)
        {
            search_word = llStringTrim(llGetSubString(msg, llStringLength(search_test_a), -1), STRING_TRIM);
            if(llSubStringIndex(llToUpper(string_example), llToUpper(search_word)) != NOT_FOUND)
            {
                llSay(PUBLIC_CHANNEL, "I have found the word " + "''" + search_word + "''" + " in the example string");
            }
            else
            {
                llSay(PUBLIC_CHANNEL, "I cannot find the word " + "''" + search_word + "''" + " in the example string.");
            }
        }
        if(llSubStringIndex(msg, search_test_b) != NOT_FOUND)
        {
            search_word = llStringTrim(llGetSubString(msg, 0, (llSubStringIndex(msg, search_test_b)-1)), STRING_TRIM);
            if(llSubStringIndex(string_example, search_word) != NOT_FOUND)
            {
                llSay(PUBLIC_CHANNEL, "I have found the word " + "''" + search_word + "''" + " in the example string");
            }
            else
            {
                llSay(PUBLIC_CHANNEL, "I cannot find the word " + "''" + search_word + "''" + " in the example string.");
            }
        }
    }
}

Helper functions

Section titled “Helper functions”

Tests to see if one string contains a copy of another:

\1. Concise & conventional:

integer contains(string haystack, string needle) // http://wiki.secondlife.com/wiki/llSubStringIndex
{
    return 0 <= llSubStringIndex(haystack, needle);
}
integer startswith(string haystack, string needle) // http://wiki.secondlife.com/wiki/llSubStringIndex
{
    return llDeleteSubString(haystack, llStringLength(needle), 0x7FFFFFF0) == needle;
}
integer endswith(string haystack, string needle) // http://wiki.secondlife.com/wiki/llSubStringIndex
{
    return llDeleteSubString(haystack, 0x8000000F, ~llStringLength(needle)) == needle;
}

Note: Some of the snippets above return a result without ever calling llSubStringIndex.

\2. Clever & smaller (calculates contains in ~54 bytes rather than ~60):

integer contains(string haystack, string needle) // http://wiki.secondlife.com/wiki/llSubStringIndex
{
    return ~llSubStringIndex(haystack, needle);
}

Note: The llSubStringIndex function returns -1 only when not found and the ~ operator returns zero only for -1, so the clever combination ~llSubStringIndex returns zero only for not found, else nonzero for found.

Note: Smaller was not noticeably faster or slower when our Code Racer and Efficiency Tester harnesses measured the expression { contains(“wiki.secondlife.com”, “wiki”); }.

See also

Section titled “See also”

Functions

Section titled “Functions”
Original wiki source

Some wiki templates and tables need their original context. View this article on the Second Life Wiki. Technical wording and examples are retained from the source; historical guidance may differ from current behavior.

From the Second Life Wiki

Community documentation adapted from LlSubStringIndex, by Linden Research, Inc. and contributing residents.View contributors and history.

Imported wiki revision:

Licensed under CC BY-SA 3.0. Last wiki edit: .Formatting and links have been adapted for this site; API metadata follows the LSL definitions.