1 files changed, 37 insertions, 0 deletions
diff --git a/src/prelude.rs b/src/prelude.rs
index 6789a1f..c647591 100644
--- a/src/prelude.rs
+++ b/src/prelude.rs
@@ -9,3 +9,40 @@ pub use std::os::unix::ffi::{OsStrExt as _, OsStringExt as _};
 pub use std::os::unix::io::{AsRawFd as _, FromRawFd as _, IntoRawFd as _};
 pub use std::os::unix::process::ExitStatusExt as _;
 pub use users::os::unix::UserExt as _;
+
+pub use ext::Result as _;
+
+mod ext {
+    pub trait Result {
+        type T;
+        type E;
+
+        fn allow(self, allow_e: Self::E) -> Self;
+        fn allow_with(self, allow_e: Self::E, default_t: Self::T) -> Self;
+    }
+
+    impl<T, E> Result for std::result::Result<T, E>
+    where
+        T: std::default::Default,
+        E: std::cmp::PartialEq,
+    {
+        type T = T;
+        type E = E;
+
+        fn allow(self, allow_e: Self::E) -> Self {
+            self.or_else(|e| {
+                if e == allow_e {
+                    Ok(std::default::Default::default())
+                } else {
+                    Err(e)
+                }
+            })
+        }
+
+        fn allow_with(self, allow_e: Self::E, default_t: Self::T) -> Self {
+            self.or_else(
+                |e| if e == allow_e { Ok(default_t) } else { Err(e) },
+            )
+        }
+    }
+}