Difference between revisions of "LlStringTrim"

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(Undo revision 30041 by Revolution Perenti That example is better for notecard reading then how to use llStringTrim, it's overkill)
(Noted that llList2Json also trims strings)
 
(19 intermediate revisions by 12 users not shown)
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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
 
! title="Value" {{!}}
 
! title="Value" {{!}}
! 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(src, STRING_TRIM_HEAD);
+
         string trim_left = llStringTrim(message, STRING_TRIM_HEAD);
         string trim_right = llStringTrim(src, STRING_TRIM_HEAD);
+
         string trim_right = llStringTrim(message, STRING_TRIM_TAIL);
         string trim = llStringTrim(src, STRING_TRIM);
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         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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|also_events
 
|also_events
 
|also_articles
 
|also_articles
|history
+
|history=
*Introduced in 1.13.4 onwards...
+
*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

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 );