llSubStringIndex
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Summary
Function: integer llSubStringIndex( string source, string pattern );| 181 | Function ID |
| 0.0 | Forced Delay |
| 10.0 | Energy |
Returns an integer that is the index of the first instance of pattern in source.
| • string | source | – | what to search in (haystack) | |
| • string | pattern | – | what to search for (needle) |
If pattern is not found in source, -1 is returned.
The index of the first character in the string is 0
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
<lsl> default {
touch_start(integer num_detected)
{
string name = llDetectedName(0);
integer spaceIndex = llSubStringIndex(name, " ");
// no conditional check is needed for (spaceIndex == -1) // 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."); }
} </lsl> <lsl> 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)
llInstantMessage(avatarKey, "Hello, I see you!");
}
while (++index < num_detected);
}
} </lsl>
Basic Example: <lsl>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.");
}</lsl>
String Cheese
<lsl>//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.");
}
}
}
}</lsl>
Useful Snippets
Tests to see if one string contains a copy of another:
1. Concise & conventional:
<lsl> integer contains(string haystack, string needle) // http://wiki.secondlife.com/wiki/llSubStringIndex {
return 0 <= llSubStringIndex(haystack, needle);
} </lsl>
<lsl>integer startswith(string haystack, string needle) // http://wiki.secondlife.com/wiki/llSubStringIndex {
return llDeleteSubString(haystack, llStringLength(needle), 0x7FFFFFF0) == needle;
}</lsl>
<lsl>integer endswith(string haystack, string needle) // http://wiki.secondlife.com/wiki/llSubStringIndex {
return llDeleteSubString(haystack, 0x8000000F, ~llStringLength(needle)) == needle;
}</lsl>
Note: Some of the snippets above return a result without ever calling llSubStringIndex.
2. Clever & smaller (calculates contains in ~54 bytes rather than ~60):
<lsl>integer contains(string haystack, string needle) // http://wiki.secondlife.com/wiki/llSubStringIndex {
return ~llSubStringIndex(haystack, needle);
}</lsl>
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
Functions
| • | llListFindList | – | Find a list in another list | |
| • | llGetSubString | – | Copy out part of a string of characters | |
| • | uSubStringLastIndex | – | Returns an integer that is the index of the last pattern in source. |
Deep Notes
Search JIRA for related Issues
Signature |
|---|
function integer llSubStringIndex( string source, string pattern ); |