Move Try to module.

Author: Clar Charr

src/libcore/ops/mod.rs

@@ -152,6 +152,7 @@ mod bit;
 mod function;
 mod place;
 mod range;
+mod try;
 
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use self::arith::{Add, Sub, Mul, Div, Rem, Neg};
@@ -172,6 +173,12 @@ pub use self::range::{Range, RangeFrom, RangeFull, RangeTo};
 #[unstable(feature = "inclusive_range", reason = "recently added, follows RFC", issue = "28237")]
 pub use self::range::{RangeInclusive, RangeToInclusive};
 
+#[unstable(feature = "question_mark_carrier", issue = "31436")]
+#[cfg(stage0)]
+pub use self::try::Carrier;
+#[unstable(feature = "try_trait", issue = "42327")]
+pub use self::try::Try;
+
 #[unstable(feature = "placement_new_protocol", issue = "27779")]
 pub use self::place::{Place, Placer, InPlace, Boxed, BoxPlace};
 
@@ -593,105 +600,3 @@ impl<T: ?Sized+Unsize<U>, U: ?Sized> CoerceUnsized<*const U> for *mut T {}
 // *const T -> *const U
 #[unstable(feature = "coerce_unsized", issue = "27732")]
 impl<T: ?Sized+Unsize<U>, U: ?Sized> CoerceUnsized<*const U> for *const T {}
-
-/// This trait has been superseded by the `Try` trait, but must remain
-/// here as `?` is still lowered to it in stage0 .
-#[cfg(stage0)]
-#[unstable(feature = "question_mark_carrier", issue = "31436")]
-pub trait Carrier {
-    /// The type of the value when computation succeeds.
-    type Success;
-    /// The type of the value when computation errors out.
-    type Error;
-
-    /// Create a `Carrier` from a success value.
-    fn from_success(_: Self::Success) -> Self;
-
-    /// Create a `Carrier` from an error value.
-    fn from_error(_: Self::Error) -> Self;
-
-    /// Translate this `Carrier` to another implementation of `Carrier` with the
-    /// same associated types.
-    fn translate<T>(self) -> T where T: Carrier<Success=Self::Success, Error=Self::Error>;
-}
-
-#[cfg(stage0)]
-#[unstable(feature = "question_mark_carrier", issue = "31436")]
-impl<U, V> Carrier for Result<U, V> {
-    type Success = U;
-    type Error = V;
-
-    fn from_success(u: U) -> Result<U, V> {
-        Ok(u)
-    }
-
-    fn from_error(e: V) -> Result<U, V> {
-        Err(e)
-    }
-
-    fn translate<T>(self) -> T
-        where T: Carrier<Success=U, Error=V>
-    {
-        match self {
-            Ok(u) => T::from_success(u),
-            Err(e) => T::from_error(e),
-        }
-    }
-}
-
-struct _DummyErrorType;
-
-impl Try for _DummyErrorType {
-    type Ok = ();
-    type Error = ();
-
-    fn into_result(self) -> Result<Self::Ok, Self::Error> {
-        Ok(())
-    }
-
-    fn from_ok(_: ()) -> _DummyErrorType {
-        _DummyErrorType
-    }
-
-    fn from_error(_: ()) -> _DummyErrorType {
-        _DummyErrorType
-    }
-}
-
-/// A trait for customizing the behaviour of the `?` operator.
-///
-/// A type implementing `Try` is one that has a canonical way to view it
-/// in terms of a success/failure dichotomy.  This trait allows both
-/// extracting those success or failure values from an existing instance and
-/// creating a new instance from a success or failure value.
-#[unstable(feature = "try_trait", issue = "42327")]
-pub trait Try {
-    /// The type of this value when viewed as successful.
-    #[unstable(feature = "try_trait", issue = "42327")]
-    type Ok;
-    /// The type of this value when viewed as failed.
-    #[unstable(feature = "try_trait", issue = "42327")]
-    type Error;
-
-    /// Applies the "?" operator. A return of `Ok(t)` means that the
-    /// execution should continue normally, and the result of `?` is the
-    /// value `t`. A return of `Err(e)` means that execution should branch
-    /// to the innermost enclosing `catch`, or return from the function.
-    ///
-    /// If an `Err(e)` result is returned, the value `e` will be "wrapped"
-    /// in the return type of the enclosing scope (which must itself implement
-    /// `Try`). Specifically, the value `X::from_error(From::from(e))`
-    /// is returned, where `X` is the return type of the enclosing function.
-    #[unstable(feature = "try_trait", issue = "42327")]
-    fn into_result(self) -> Result<Self::Ok, Self::Error>;
-
-    /// Wrap an error value to construct the composite result. For example,
-    /// `Result::Err(x)` and `Result::from_error(x)` are equivalent.
-    #[unstable(feature = "try_trait", issue = "42327")]
-    fn from_error(v: Self::Error) -> Self;
-
-    /// Wrap an OK value to construct the composite result. For example,
-    /// `Result::Ok(x)` and `Result::from_ok(x)` are equivalent.
-    #[unstable(feature = "try_trait", issue = "42327")]
-    fn from_ok(v: Self::Ok) -> Self;
-}

src/libcore/ops/try.rs

@@ -0,0 +1,111 @@
+// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+/// This trait has been superseded by the `Try` trait, but must remain
+/// here as `?` is still lowered to it in stage0 .
+#[cfg(stage0)]
+#[unstable(feature = "question_mark_carrier", issue = "31436")]
+pub trait Carrier {
+    /// The type of the value when computation succeeds.
+    type Success;
+    /// The type of the value when computation errors out.
+    type Error;
+
+    /// Create a `Carrier` from a success value.
+    fn from_success(_: Self::Success) -> Self;
+
+    /// Create a `Carrier` from an error value.
+    fn from_error(_: Self::Error) -> Self;
+
+    /// Translate this `Carrier` to another implementation of `Carrier` with the
+    /// same associated types.
+    fn translate<T>(self) -> T where T: Carrier<Success=Self::Success, Error=Self::Error>;
+}
+
+#[cfg(stage0)]
+#[unstable(feature = "question_mark_carrier", issue = "31436")]
+impl<U, V> Carrier for Result<U, V> {
+    type Success = U;
+    type Error = V;
+
+    fn from_success(u: U) -> Result<U, V> {
+        Ok(u)
+    }
+
+    fn from_error(e: V) -> Result<U, V> {
+        Err(e)
+    }
+
+    fn translate<T>(self) -> T
+        where T: Carrier<Success=U, Error=V>
+    {
+        match self {
+            Ok(u) => T::from_success(u),
+            Err(e) => T::from_error(e),
+        }
+    }
+}
+
+struct _DummyErrorType;
+
+impl Try for _DummyErrorType {
+    type Ok = ();
+    type Error = ();
+
+    fn into_result(self) -> Result<Self::Ok, Self::Error> {
+        Ok(())
+    }
+
+    fn from_ok(_: ()) -> _DummyErrorType {
+        _DummyErrorType
+    }
+
+    fn from_error(_: ()) -> _DummyErrorType {
+        _DummyErrorType
+    }
+}
+
+/// A trait for customizing the behaviour of the `?` operator.
+///
+/// A type implementing `Try` is one that has a canonical way to view it
+/// in terms of a success/failure dichotomy.  This trait allows both
+/// extracting those success or failure values from an existing instance and
+/// creating a new instance from a success or failure value.
+#[unstable(feature = "try_trait", issue = "42327")]
+pub trait Try {
+    /// The type of this value when viewed as successful.
+    #[unstable(feature = "try_trait", issue = "42327")]
+    type Ok;
+    /// The type of this value when viewed as failed.
+    #[unstable(feature = "try_trait", issue = "42327")]
+    type Error;
+
+    /// Applies the "?" operator. A return of `Ok(t)` means that the
+    /// execution should continue normally, and the result of `?` is the
+    /// value `t`. A return of `Err(e)` means that execution should branch
+    /// to the innermost enclosing `catch`, or return from the function.
+    ///
+    /// If an `Err(e)` result is returned, the value `e` will be "wrapped"
+    /// in the return type of the enclosing scope (which must itself implement
+    /// `Try`). Specifically, the value `X::from_error(From::from(e))`
+    /// is returned, where `X` is the return type of the enclosing function.
+    #[unstable(feature = "try_trait", issue = "42327")]
+    fn into_result(self) -> Result<Self::Ok, Self::Error>;
+
+    /// Wrap an error value to construct the composite result. For example,
+    /// `Result::Err(x)` and `Result::from_error(x)` are equivalent.
+    #[unstable(feature = "try_trait", issue = "42327")]
+    fn from_error(v: Self::Error) -> Self;
+
+    /// Wrap an OK value to construct the composite result. For example,
+    /// `Result::Ok(x)` and `Result::from_ok(x)` are equivalent.
+    #[unstable(feature = "try_trait", issue = "42327")]
+    fn from_ok(v: Self::Ok) -> Self;
+}