Setup some publish/subscribe pattern

.gitignore

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+/target
+/Cargo.lock

Cargo.toml

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+[package]
+
+name = "rustfrp"
+version = "0.0.1"
+authors = ["Eduard Bopp <eduard.bopp@aepsil0n.de>"]

src/lib.rs

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+mod subject;

src/subject.rs

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+use std::sync::mpsc::{channel, Sender, Receiver};
+
+pub struct Subject<A: Send + Clone> {
+    senders: Vec<Sender<A>>,
+}
+
+impl<A: Send + Clone> Subject<A> {
+    pub fn new() -> Subject<A> {
+        Subject { senders: Vec::new() }
+    }
+
+    pub fn listen(&mut self) -> Receiver<A> {
+        let (tx, rx) = channel::<A>();
+        self.senders.push(tx);
+        rx
+    }
+
+    pub fn send(&mut self, a: A) {
+        let mut idx_to_remove = vec!();
+        for (k, tx) in self.senders.iter().enumerate() {
+            match tx.send(a.clone()) {
+                Ok(_) => (),
+                Err(_) => idx_to_remove.push(k),
+            }
+        }
+        for k in idx_to_remove.into_iter() {
+            self.senders.remove(k);
+        }
+    }
+}
+
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn two_receivers() {
+        let mut sub = Subject::new();
+        let r1 = sub.listen();
+        let r2 = sub.listen();
+        sub.send(3);
+        assert_eq!(r1.recv(), Ok(3));
+        assert_eq!(r2.recv(), Ok(3));
+    }
+}