Add eyre::Ok (#91)

This change introduces the function eyre::Ok(), a backport of the convenience function anyhow::Ok() which avoids a lengthy turbofish when producing an Ok(()).

eyre/src/lib.rs

@@ -709,7 +709,7 @@ pub trait EyreHandler: core::any::Any + Send + Sync {
             }
         }
 
-        Ok(())
+        Result::Ok(())
     }
 
     /// Store the location of the caller who constructed this error report
@@ -831,7 +831,7 @@ impl EyreHandler for DefaultHandler {
             }
         }
 
-        Ok(())
+        Result::Ok(())
     }
 
     #[cfg(track_caller)]
@@ -1193,6 +1193,29 @@ pub trait ContextCompat<T>: context::private::Sealed {
         F: FnOnce() -> D;
 }
 
+/// Equivalent to Ok::<_, eyre::Error>(value).
+///
+/// This simplifies creation of an eyre::Result in places where type inference
+/// cannot deduce the `E` type of the result &mdash; without needing to write
+/// `Ok::<_, eyre::Error>(value)`.
+///
+/// One might think that `eyre::Result::Ok(value)` would work in such cases
+/// but it does not.
+///
+/// ```console
+/// error[E0282]: type annotations needed for `std::result::Result<i32, E>`
+///   --> src/main.rs:11:13
+///    |
+/// 11 |     let _ = eyre::Result::Ok(1);
+///    |         -   ^^^^^^^^^^^^^^^^ cannot infer type for type parameter `E` declared on the enum `Result`
+///    |         |
+///    |         consider giving this pattern the explicit type `std::result::Result<i32, E>`, where the type parameter `E` is specified
+/// ```
+#[allow(non_snake_case)]
+pub fn Ok<T>(t: T) -> Result<T> {
+    Result::Ok(t)
+}
+
 // Not public API. Referenced by macro-generated code.
 #[doc(hidden)]
 pub mod private {