1 files changed, 13 insertions, 0 deletions
diff --git a/futures/src/executor.rs b/futures/src/executor.rs
index b2ff043e..c2b9cc72 100644
--- a/futures/src/executor.rs
+++ b/futures/src/executor.rs
@@ -29,13 +29,26 @@ pub use wasm_bindgen::WasmBindgen;
 
 use futures::Future;
 
+/// A type that can run futures.
 pub trait Executor: Sized {
+    /// Creates a new [`Executor`].
+    ///
+    /// [`Executor`]: trait.Executor.html
     fn new() -> Result<Self, futures::io::Error>
     where
         Self: Sized;
 
+    /// Spawns a future in the [`Executor`].
+    ///
+    /// [`Executor`]: trait.Executor.html
     fn spawn(&self, future: impl Future<Output = ()> + Send + 'static);
 
+    /// Runs the given closure inside the [`Executor`].
+    ///
+    /// Some executors, like `tokio`, require some global state to be in place
+    /// before creating futures. This method can be leveraged to set up this
+    /// global state, call a function, restore the state, and obtain the result
+    /// of the call.
     fn enter<R>(&self, f: impl FnOnce() -> R) -> R {
         f()
     }