diff --git a/README.md b/README.md
index cde2cac..426ae06 100644
--- a/README.md
+++ b/README.md
@@ -65,6 +65,19 @@ Inside `speculate! { ... }`, you can have any "Item", like `static`, `const`,
   }
   ```
 
+  You can also declare an error type that the tests can fail with, which implicitly makes those test return `Result<(), E>`:
+
+  ```rust
+  use std::fs;
+  speculate! {
+      errtype(Error)
+
+      it "has i/o setup" {
+          fs::write("/some/file", "with content")?;
+          assert_eq!(file_reader()?, "with_content");
+      }
+  }
+  ```
 * `bench` - contains benchmarks.
 
   For example:
diff --git a/src/lib.rs b/src/lib.rs
index b73febb..01197ef 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -85,6 +85,19 @@ fn get_root_name() -> proc_macro2::Ident {
 ///   }
 ///   # }
 ///   ```
+/// You can also declare an error type that the tests can fail with, which implicitly makes those test return `Result<(), E>`:
+///
+/// ```rust
+/// use std::fs;
+/// speculate! {
+///     errtype(Error)
+///
+///     it "has i/o setup" {
+///         fs::write("/some/file", "with content")?;
+///         assert_eq!(file_reader()?, "with_content");
+///     }
+/// }
+/// ```
 ///
 /// * `bench` - contains benchmarks (using [`Bencher`](https://doc.rust-lang.org/test/struct.Bencher.html)).
 ///