Difference between revisions of "LlStringTrim"

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(Noted that llList2Json also trims strings)
 
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{{#vardefine:type|function}}
 
{{LSL_Function
 
{{LSL_Function
 
|func_id=330|func_sleep=0.0|func_energy=10.0
 
|func_id=330|func_sleep=0.0|func_energy=10.0
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|func_footnote
 
|func_footnote
 
|func_desc
 
|func_desc
|return_text=that is '''src''' with leading and/or trailing spaces trimmed from it.
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|return_text=that is {{LSLP|src}} with leading and/or trailing white space (spaces, tabs, and line feeds) trimmed from it.
 
|spec
 
|spec
 
|caveats
 
|caveats
 
|constants=
 
|constants=
{{{!}}{{Prettytable}}
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{{{!}} class="sortable" {{Prettytable|style=margin-top:0;}}
 
{{!}}-{{Hl2}}
 
{{!}}-{{Hl2}}
{{!}}colspan="2"{{!}}Constant
+
! {{!}} Constant
{{!}}Description
+
! title="Value" {{!}}
 +
! class="unsortable"{{!}} Description
 
{{!}}-
 
{{!}}-
{{!}}[[STRING_TRIM_HEAD]]
+
{{!}}{{LSL Const|STRING_TRIM_HEAD|integer|1|hex=0x1|c=Trims white space off the beginning.}}
{{!}}0x01
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{{!}}{{#var:value}}
{{!}}Trims spaces off the beginning.
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{{!}}{{#var:comment}}
 
{{!}}-
 
{{!}}-
{{!}}[[STRING_TRIM_TAIL]]
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{{!}}{{LSL Const|STRING_TRIM_TAIL|integer|2|hex=0x2|c=Trims white space off the end.}}
{{!}}0x02
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{{!}}{{#var:value}}
{{!}}Trims spaces off the end
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{{!}}{{#var:comment}}
 
{{!}}-
 
{{!}}-
{{!}}[[STRING_TRIM]]
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{{!}}{{LSL Const|STRING_TRIM|integer|3|hex=0x3|c=Trims white space off the beginning and end.}}
{{!}}0x03
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{{!}}{{#var:value}}
{{!}}Trims spaces off the beginning and end.
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{{!}}{{#var:comment}}
 
{{!}}}
 
{{!}}}
|examples
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|examples=
 +
 
 +
Whenever you are accepting unstructured input from a user -- whether via chat or via a notecard -- it is a good idea to always full trim it:
 +
 
 +
<source lang="lsl2">llStringTrim("User input", STRING_TRIM);</source>
 +
 
 +
 
 +
This example returns the number of leading and trailing 'white space' characters on a string that were removed (not particularly useful but shows how to use the function).
 +
<source lang="lsl2">
 +
default
 +
{
 +
    state_entry()
 +
    {
 +
        llListen(4, "", llGetOwner(), "");
 +
    }
 +
 
 +
    on_rez(integer start_param)
 +
    {
 +
        llResetScript();
 +
    }
 +
 
 +
    listen(integer channel, string name, key id, string message)
 +
    {     
 +
        //track the length
 +
        integer length = llStringLength(message);
 +
       
 +
        //trim message (not necessary to store these to variables but makes reading easier)
 +
        string trim_left  = llStringTrim(message, STRING_TRIM_HEAD);
 +
        string trim_right = llStringTrim(message, STRING_TRIM_TAIL);
 +
        string trim_both  = llStringTrim(message, STRING_TRIM);
 +
 
 +
        //output the results
 +
        llOwnerSay("Initial length  = " + (string)length +
 +
                "\nLeading Spaces  = " + (string)(length - llStringLength(trim_left))+
 +
                "\nTrailing Spaces = " + (string)(length - llStringLength(trim_right))+
 +
                "\nTrimmed Message = \"" + trim_both + "\"");
 +
    }
 +
}
 +
</source>
 
|helpers
 
|helpers
 
|also_functions
 
|also_functions
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|also_events
 
|also_events
 
|also_articles
 
|also_articles
|notes=This function is available in 1.13.4
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|history=
 +
*Introduced in 1.13.4
 +
Date of release [[ Release_Notes/Second_Life_Release/1.15#Release_Notes_for_Second_Life_1.15.0.282.29_April_25.2C_2007 | 25-04-2007 ]]
 +
|notes=
 +
Aside from white space at the beginning and / or end, the actual string will be unaffected. This means too, though, that extraneous spaces within the string -- for instance, a mistaken double-space type -- will not be corrected.
 +
 
 +
The following will remove all double spaces and leading and trailing spaces.
 +
<source lang="lsl2">llDumpList2String(llParseString2List(src, [" "], []), " "); //works but can use a large quantity of memory</source>
 +
 
 +
This method strips spaces from the sentence and may use less memory
 +
<source lang="lsl2">
 +
//Added By To-mos Codewarrior
 +
string str1 = "some words to remove the spaces from";
 +
integer index;
 +
while(~index=llSubStringIndex(str1," ")) {
 +
    data=llDeleteSubString(str1,index,index);
 +
}
 +
</source>
 +
The following will do the same:
 +
<source lang="lsl2">(string)llParseString2List(src, [" "], []); //works but can use a large quantity of memory</source>
 +
 
 +
[[llList2Json]] also trims strings contained in the list. Thus, an easy way to trim an entire list of strings is:
 +
<source lang="lsl2">
 +
list l = ["  a  ", " b", "c ", " d "];
 +
list trimmedList = llJson2List(llList2Json(JSON_ARRAY, l));
 +
</source>
 +
 
  
It is no mistake that <code>(STRING_TRIM_HEAD {{!}} STRING_TRIM_TAIL) == STRING_TRIM</code>
 
 
|deprecated
 
|deprecated
 
|cat1=String
 
|cat1=String

Latest revision as of 18:11, 20 April 2017

Summary

Function: string llStringTrim( string src, integer type );

Returns a string that is src with leading and/or trailing white space (spaces, tabs, and line feeds) trimmed from it.

• string src
• integer type STRING_TRIM* flag(s)
Constant Description
STRING_TRIM_HEAD 0x1 Trims white space off the beginning.
STRING_TRIM_TAIL 0x2 Trims white space off the end.
STRING_TRIM 0x3 Trims white space off the beginning and end.

Examples

Whenever you are accepting unstructured input from a user -- whether via chat or via a notecard -- it is a good idea to always full trim it:

llStringTrim("User input", STRING_TRIM);


This example returns the number of leading and trailing 'white space' characters on a string that were removed (not particularly useful but shows how to use the function).

default
{
    state_entry()
    {
        llListen(4, "", llGetOwner(), "");
    }
 
    on_rez(integer start_param)
    {
        llResetScript();
    }
 
    listen(integer channel, string name, key id, string message)
    {       
        //track the length
        integer length = llStringLength(message);
 
        //trim message (not necessary to store these to variables but makes reading easier)
        string trim_left  = llStringTrim(message, STRING_TRIM_HEAD);
        string trim_right = llStringTrim(message, STRING_TRIM_TAIL);
        string trim_both  = llStringTrim(message, STRING_TRIM);
 
        //output the results
        llOwnerSay("Initial length  = " + (string)length +
                 "\nLeading Spaces  = " + (string)(length - llStringLength(trim_left))+
                 "\nTrailing Spaces = " + (string)(length - llStringLength(trim_right))+
                 "\nTrimmed Message = \"" + trim_both + "\"");
    }
}

Notes

Aside from white space at the beginning and / or end, the actual string will be unaffected. This means too, though, that extraneous spaces within the string -- for instance, a mistaken double-space type -- will not be corrected.

The following will remove all double spaces and leading and trailing spaces.

llDumpList2String(llParseString2List(src, [" "], []), " "); //works but can use a large quantity of memory

This method strips spaces from the sentence and may use less memory

//Added By To-mos Codewarrior
string str1 = "some words to remove the spaces from";
integer index;
while(~index=llSubStringIndex(str1," ")) {
    data=llDeleteSubString(str1,index,index);
}

The following will do the same:

(string)llParseString2List(src, [" "], []); //works but can use a large quantity of memory

llList2Json also trims strings contained in the list. Thus, an easy way to trim an entire list of strings is:

list l = ["  a  ", " b", "c ", " d "];
list trimmedList = llJson2List(llList2Json(JSON_ARRAY, l));

Deep Notes

History

  • Introduced in 1.13.4
Date of release 25-04-2007

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Signature

function string llStringTrim( string src, integer type );