Difference between revisions of "LlStringTrim"

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(Noted that llList2Json also trims strings)
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|func_footnote
|func_footnote
|func_desc
|func_desc
|return_text=that is '''src''' with leading and/or trailing white space (spaces, tabs, and line feeds) trimmed from it.
|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=
{{{!}} class="sortable" {{Prettytable}}
{{{!}} class="sortable" {{Prettytable|style=margin-top:0;}}
{{!}}-{{Hl2}}
{{!}}-{{Hl2}}
! {{!}} Constant
! {{!}} Constant
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! class="unsortable"{{!}} Description
! class="unsortable"{{!}} Description
{{!}}-
{{!}}-
{{!}}{{LSL Const|STRING_TRIM_HEAD|integer|1|hex=0x1|c=Trims spaces off the beginning.}}
{{!}}{{LSL Const|STRING_TRIM_HEAD|integer|1|hex=0x1|c=Trims white space off the beginning.}}
{{!}}{{#var:value}}
{{!}}{{#var:value}}
{{!}}{{#var:comment}}
{{!}}{{#var:comment}}
{{!}}-
{{!}}-
{{!}}{{LSL Const|STRING_TRIM_TAIL|integer|2|hex=0x2|c=Trims spaces off the end.}}
{{!}}{{LSL Const|STRING_TRIM_TAIL|integer|2|hex=0x2|c=Trims white space off the end.}}
{{!}}{{#var:value}}
{{!}}{{#var:value}}
{{!}}{{#var:comment}}
{{!}}{{#var:comment}}
{{!}}-
{{!}}-
{{!}}{{LSL Const|STRING_TRIM|integer|3|hex=0x3|c=Trims spaces off the beginning and end.}}
{{!}}{{LSL Const|STRING_TRIM|integer|3|hex=0x3|c=Trims white space off the beginning and end.}}
{{!}}{{#var:value}}
{{!}}{{#var:value}}
{{!}}{{#var:comment}}
{{!}}{{#var:comment}}
{{!}}}
{{!}}}
|examples=
|examples=
Returns the number of leading and trailing spaces on a string (not particularly useful but shows how to use the function).
 
<pre>
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
default
{
{
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         llListen(4, "", llGetOwner(), "");
         llListen(4, "", llGetOwner(), "");
     }
     }
     on_rez(integer a)
 
     on_rez(integer start_param)
     {
     {
         llResetScript();
         llResetScript();
     }
     }
     listen(integer chan, string name, key id, string msg)
 
     {
     listen(integer channel, string name, key id, string message)
        //test for and remove wrapping single or double quotes
     {      
        if(~llSubStringIndex("'\"", llGetSubString(msg,0,0)))
            if(llGetSubString(msg,-1,-1) == llGetSubString(msg,0,0))
                msg = llDeleteSubString(msg, -1, 0);
       
         //track the length
         //track the length
         integer length = llStringLength(msg);
         integer length = llStringLength(message);
          
          
         //trim msg (not necessary to store these to variables but makes reading easier)
         //trim message (not necessary to store these to variables but makes reading easier)
         string trim_left = llStringTrim(msg, STRING_TRIM_HEAD);
         string trim_left = llStringTrim(message, STRING_TRIM_HEAD);
         string trim_right = llStringTrim(msg, STRING_TRIM_HEAD);
         string trim_right = llStringTrim(message, STRING_TRIM_TAIL);
         string trim = llStringTrim(msg, STRING_TRIM);
         string trim_both  = llStringTrim(message, STRING_TRIM);


         //output the results
         //output the results
         llOwnerSay("Initial length = " + (string)length +
         llOwnerSay("Initial length = " + (string)length +
                 "\nLeading Spaces = " + (string)(length - llStringLength(trim_left))+
                 "\nLeading Spaces = " + (string)(length - llStringLength(trim_left))+
                 "\nTrailing Spaces = " + (string)(length - llStringLength(trim_right))+
                 "\nTrailing Spaces = " + (string)(length - llStringLength(trim_right))+
                 "\nTrimmed Message = \"" + trim + "\"");
                 "\nTrimmed Message = \"" + trim_both + "\"");
     }
     }
}
}
</pre>
</source>
|helpers
|helpers
|also_functions
|also_functions
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|history=
|history=
*Introduced in 1.13.4
*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=
|notes=
The following examples will make the same result.
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.
<pre>
 
string src = "   Duh    ";
The following will remove all double spaces and leading and trailing spaces.
st = llStringTrim(src, STRING_TRIM_HEAD);
<source lang="lsl2">llDumpList2String(llParseString2List(src, [" "], []), " "); //works but can use a large quantity of memory</source>
st = llStringTrim(st , STRING_TRIM_TAIL);
 
</pre>
This method strips spaces from the sentence and may use less memory
<pre>
<source lang="lsl2">
string src = "   Duh    ";
//Added By To-mos Codewarrior
st = llStringTrim(src, STRING_TRIM);
string str1 = "some words to remove the spaces from";
</pre>
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>
 


This is because <code>(STRING_TRIM_HEAD {{!}} STRING_TRIM_TAIL) == STRING_TRIM</code>.
|deprecated
|deprecated
|cat1=String
|cat1=String

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

Search JIRA for related Issues

Signature

function string llStringTrim( string src, integer type );