Macro define_queue_method

macro_rules! define_queue_method {
    (
        $(#[$doc:meta])*
        $method:ident, $return_type:ty, $( $var:ident : $vartype:ty ),*
    ) => { ... };
    (
        $(#[$doc:meta])*
        $method:ident, $return_type:ty, mut, $( $var:ident : $vartype:ty ),*
    ) => { ... };
}

Usage: define_queue_method!(method_name, return_type[, mut][, arg1: arg1_type, arg2: arg2_type, …])

• method_name: The name of the method to be defined (as an identifier).
• return_type: The return type of the method.
• mut (optional): Include this keyword if the method requires a mutable reference to self (&mut self).
• arg1: arg1_type, arg2: arg2_type, ... (optional): Include method parameters as a comma-separated list of name: type pairs, if the method takes any arguments.