Difference between revisions of "Category:LSL User-Defined Functions"

User-Defined Functions

This category contains custom pre-defined function contributions from the LSL community to extend the abilities of LSL. To add a wiki page to this category, include a link to this page. You may use the Template:LSL_Function (with "mode" set to user) to create the page to be added here.

Go to the Functions page to view the built-in functions.

About User-Defined Functions

LSL allows user-defined functions. The syntax is very simple:

<lsl> return_type variable_name(par1type par1name, par2type par2name,...) {

 function_statements;
 .
 .
 .
 return value_of_return_type;

}

// example with void return type:

let_prim_say_something_and_include_owner_info(string message) {

   key ownerKey = llGetOwner();
   string ownerName = llKey2Name(ownerKey);

   llSay(PUBLIC_CHANNEL, "/me (owned by " + ownerName + "): " + message);

}

default {

   state_entry()
   {
       let_prim_say_something_and_include_owner_info("Hello world!");
   }

}

// example with integer return type (actually it's a boolean)

integer is_sun_up() {

   vector sunDirection = llGetSunDirection();

   if (sunDirection.z < 0.0)
       return FALSE;

   // else
       return TRUE;

}

default {

   state_entry()
   {
       if ( is_sun_up() )
           llSay(PUBLIC_CHANNEL, "Good day!");
       else
           llSay(PUBLIC_CHANNEL, "Good night!");
   }

} </lsl>

There are no "function" or "def" keywords or function type/inheritance specifiers needed. I have not yet discovered what limits (if any) exist on the length or composition of the parameter list. Multiple types can be used, as shown in the example below. A list can be returned, so a single function can return a list with several values in it. User-defined functions will help keep scripts compact and readable, and allow rudimentary code reuse. The LSL_Style_Guide suggests that user-defined functions should be placed before the default state definition and after user-defined variables. Placing user-defined functions after the first state will result in a Syntax Error.

examples can be found linked below