Category:LSL User-Defined Functions

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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:

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!");
    }
}

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