Initial commit

src/handling/then.rs

@@ -0,0 +1,29 @@
+use crate::{
+    data,
+    fut::Fut,
+    handling::{Apply, Handler},
+};
+
+#[data(copy, ord, crate = crate)]
+pub struct Then<L, R> {
+    pub lhs: L,
+    pub rhs: R,
+}
+
+impl<I, S, L, R, N, Output> Handler<I, S, N> for Then<L, R>
+where
+    R: Send + Sync,
+    L: for<'a> Handler<I, S, Apply<&'a R, N>, Output = Output>,
+{
+    type Output = Output;
+
+    fn call(&self, state: S, in_: I, next: N) -> impl Fut<Output = Self::Output> {
+        self.lhs.call(state, in_, Apply::new(&self.rhs, next))
+    }
+}
+
+impl<L, R> Then<L, R> {
+    pub const fn new(lhs: L, rhs: R) -> Self {
+        Self { lhs, rhs }
+    }
+}