event/
lib.rs

1#![allow(dead_code)]
2
3use std::collections::BTreeMap;
4
5/// Enumerator of the Event type. Whatever type E of Event::Args you implement here is the type E that will be used for the EventPublisher.
6pub enum Event<E> {
7    Args(E),
8    Missing,
9}
10
11// To deal with handler functions - F: Rc<Box<Fn(&event<E>)>>
12/// EventPublisher. Works similarly to C#'s event publishing pattern. Event handling functions are subscribed to the publisher.
13/// Whenever the publisher fires an event it calls all subscribed event handler functions.
14/// Use event::EventPublisher::<E>::new() to construct
15pub struct EventPublisher<E> {
16    //handlers: Vec<Rc<Box<Fn(&Event<E>) + 'static>>>,
17    handlers: BTreeMap<usize, fn(&Event<E>)>,
18}
19
20impl<E> EventPublisher<E> {
21
22    /// Event publisher constructor.
23    pub fn new() -> EventPublisher<E> {
24        EventPublisher{ 
25            handlers: BTreeMap::<usize, fn(&Event<E>)>::new()
26        }
27    }
28    /// Subscribes event handler functions to the EventPublisher.
29    /// INPUT:  handler: fn(&Event<E>) handler is a pointer to a function to handle an event of the type E. The function must
30    ///     be capable of handling references to the event type set up by the publisher, rather than the raw event itself.
31    /// OUTPUT: void
32    pub fn subscribe_handler(&mut self, handler: fn(&Event<E>)){
33        let p_handler: usize;
34        unsafe{
35            p_handler = *(handler as *const usize);
36        }
37        self.handlers.insert(p_handler, handler);
38    }
39    
40    /// Unsubscribes an event handler from the publisher.
41    /// INPUT:  handler: fn(&Event<E>) handler is a pointer to a function to handle an event of the type E.
42    /// OUTPUT: bool    output is a bool of whether or not the function was found in the list of subscribed event handlers and subsequently removed.
43    pub fn unsubscribe_handler(&mut self, handler: fn(&Event<E>)) -> bool {
44        let p_handler: usize;
45        unsafe{
46            p_handler = *(handler as *const usize);
47        }
48        match self.handlers.remove(&p_handler){
49            Some(_) => true,
50            None => false,
51        }
52    }
53        
54    // TODO: Implement this concurrently
55    /// Publishes events, pushing the &Event<E> to all handler functions stored by the event publisher.
56    /// INPUT: event: &Event<E>     Reference to the Event<E> being pushed to all handling functions.
57    pub fn publish_event(&self, event: &Event<E>){
58        for (_, handler) in self.handlers.iter(){
59            handler(event);
60        }
61    }
62}
event/lib.rs

event/
lib.rs
