Revert "Stabilize the TryFrom and TryInto traits"

This reverts commit e53a2a72743810e05f58c61c9d8a4c89b712ad2e.

6 files changed, 18 insertions, 21 deletions

diff --git a/src/libcore/array.rs b/src/libcore/array.rs
index 87144c27c9e..3d24f8902bd 100644
--- a/src/libcore/array.rs
+++ b/src/libcore/array.rs
@@ -59,7 +59,7 @@ unsafe impl<T, A: Unsize<[T]>> FixedSizeArray<T> for A {
 }
 
 /// The error type returned when a conversion from a slice to an array fails.
-#[stable(feature = "try_from", since = "1.26.0")]
+#[unstable(feature = "try_from", issue = "33417")]
 #[derive(Debug, Copy, Clone)]
 pub struct TryFromSliceError(());
 
@@ -148,7 +148,7 @@ macro_rules! array_impls {
                 }
             }
 
-            #[stable(feature = "try_from", since = "1.26.0")]
+            #[unstable(feature = "try_from", issue = "33417")]
             impl<'a, T> TryFrom<&'a [T]> for &'a [T; $N] {
                 type Error = TryFromSliceError;
 
@@ -162,7 +162,7 @@ macro_rules! array_impls {
                 }
             }
 
-            #[stable(feature = "try_from", since = "1.26.0")]
+            #[unstable(feature = "try_from", issue = "33417")]
             impl<'a, T> TryFrom<&'a mut [T]> for &'a mut [T; $N] {
                 type Error = TryFromSliceError;
 
diff --git a/src/libcore/char/convert.rs b/src/libcore/char/convert.rs
index 150562a4a9b..803a924eb3a 100644
--- a/src/libcore/char/convert.rs
+++ b/src/libcore/char/convert.rs
@@ -204,7 +204,7 @@ impl FromStr for char {
 }
 
 
-#[stable(feature = "try_from", since = "1.26.0")]
+#[unstable(feature = "try_from", issue = "33417")]
 impl TryFrom<u32> for char {
     type Error = CharTryFromError;
 
@@ -219,11 +219,11 @@ impl TryFrom<u32> for char {
 }
 
 /// The error type returned when a conversion from u32 to char fails.
-#[stable(feature = "try_from", since = "1.26.0")]
+#[unstable(feature = "try_from", issue = "33417")]
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub struct CharTryFromError(());
 
-#[stable(feature = "try_from", since = "1.26.0")]
+#[unstable(feature = "try_from", issue = "33417")]
 impl fmt::Display for CharTryFromError {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         "converted integer out of range for `char`".fmt(f)
diff --git a/src/libcore/char/mod.rs b/src/libcore/char/mod.rs
index 9edc0c88756..210eceebc51 100644
--- a/src/libcore/char/mod.rs
+++ b/src/libcore/char/mod.rs
@@ -40,7 +40,7 @@ pub use self::convert::{from_u32, from_digit};
 pub use self::convert::from_u32_unchecked;
 #[stable(feature = "char_from_str", since = "1.20.0")]
 pub use self::convert::ParseCharError;
-#[stable(feature = "try_from", since = "1.26.0")]
+#[unstable(feature = "try_from", issue = "33417")]
 pub use self::convert::CharTryFromError;
 #[stable(feature = "decode_utf16", since = "1.9.0")]
 pub use self::decode::{decode_utf16, DecodeUtf16, DecodeUtf16Error};
diff --git a/src/libcore/convert.rs b/src/libcore/convert.rs
index 63721395784..7324df95bc5 100644
--- a/src/libcore/convert.rs
+++ b/src/libcore/convert.rs
@@ -322,26 +322,22 @@ pub trait From<T>: Sized {
 ///
 /// [`TryFrom`]: trait.TryFrom.html
 /// [`Into`]: trait.Into.html
-#[stable(feature = "try_from", since = "1.26.0")]
+#[unstable(feature = "try_from", issue = "33417")]
 pub trait TryInto<T>: Sized {
     /// The type returned in the event of a conversion error.
-    #[stable(feature = "try_from", since = "1.26.0")]
     type Error;
 
     /// Performs the conversion.
-    #[stable(feature = "try_from", since = "1.26.0")]
     fn try_into(self) -> Result<T, Self::Error>;
 }
 
 /// Attempt to construct `Self` via a conversion.
-#[stable(feature = "try_from", since = "1.26.0")]
+#[unstable(feature = "try_from", issue = "33417")]
 pub trait TryFrom<T>: Sized {
     /// The type returned in the event of a conversion error.
-    #[stable(feature = "try_from", since = "1.26.0")]
     type Error;
 
     /// Performs the conversion.
-    #[stable(feature = "try_from", since = "1.26.0")]
     fn try_from(value: T) -> Result<Self, Self::Error>;
 }
 
@@ -409,7 +405,7 @@ impl<T> From<T> for T {
 
 
 // TryFrom implies TryInto
-#[stable(feature = "try_from", since = "1.26.0")]
+#[unstable(feature = "try_from", issue = "33417")]
 impl<T, U> TryInto<U> for T where U: TryFrom<T>
 {
     type Error = U::Error;
@@ -421,7 +417,7 @@ impl<T, U> TryInto<U> for T where U: TryFrom<T>
 
 // Infallible conversions are semantically equivalent to fallible conversions
 // with an uninhabited error type.
-#[stable(feature = "try_from", since = "1.26.0")]
+#[unstable(feature = "try_from", issue = "33417")]
 impl<T, U> TryFrom<U> for T where T: From<U> {
     type Error = !;
 
diff --git a/src/libcore/num/mod.rs b/src/libcore/num/mod.rs
index f2e8caaad14..801e2328a4b 100644
--- a/src/libcore/num/mod.rs
+++ b/src/libcore/num/mod.rs
@@ -4192,7 +4192,7 @@ macro_rules! from_str_radix_int_impl {
 from_str_radix_int_impl! { isize i8 i16 i32 i64 i128 usize u8 u16 u32 u64 u128 }
 
 /// The error type returned when a checked integral type conversion fails.
-#[stable(feature = "try_from", since = "1.26.0")]
+#[unstable(feature = "try_from", issue = "33417")]
 #[derive(Debug, Copy, Clone)]
 pub struct TryFromIntError(());
 
@@ -4207,14 +4207,14 @@ impl TryFromIntError {
     }
 }
 
-#[stable(feature = "try_from", since = "1.26.0")]
+#[unstable(feature = "try_from", issue = "33417")]
 impl fmt::Display for TryFromIntError {
     fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
         self.__description().fmt(fmt)
     }
 }
 
-#[stable(feature = "try_from", since = "1.26.0")]
+#[unstable(feature = "try_from", issue = "33417")]
 impl From<!> for TryFromIntError {
     fn from(never: !) -> TryFromIntError {
         never
@@ -4224,7 +4224,7 @@ impl From<!> for TryFromIntError {
 // only negative bounds
 macro_rules! try_from_lower_bounded {
     ($source:ty, $($target:ty),*) => {$(
-        #[stable(feature = "try_from", since = "1.26.0")]
+        #[unstable(feature = "try_from", issue = "33417")]
         impl TryFrom<$source> for $target {
             type Error = TryFromIntError;
 
@@ -4243,7 +4243,7 @@ macro_rules! try_from_lower_bounded {
 // unsigned to signed (only positive bound)
 macro_rules! try_from_upper_bounded {
     ($source:ty, $($target:ty),*) => {$(
-        #[stable(feature = "try_from", since = "1.26.0")]
+        #[unstable(feature = "try_from", issue = "33417")]
         impl TryFrom<$source> for $target {
             type Error = TryFromIntError;
 
@@ -4262,7 +4262,7 @@ macro_rules! try_from_upper_bounded {
 // all other cases
 macro_rules! try_from_both_bounded {
     ($source:ty, $($target:ty),*) => {$(
-        #[stable(feature = "try_from", since = "1.26.0")]
+        #[unstable(feature = "try_from", issue = "33417")]
         impl TryFrom<$source> for $target {
             type Error = TryFromIntError;
 
diff --git a/src/libcore/tests/lib.rs b/src/libcore/tests/lib.rs
index bb875c7219a..3b080689cb3 100644
--- a/src/libcore/tests/lib.rs
+++ b/src/libcore/tests/lib.rs
@@ -36,6 +36,7 @@
 #![feature(str_internals)]
 #![feature(test)]
 #![feature(trusted_len)]
+#![feature(try_from)]
 #![feature(try_trait)]
 #![feature(exact_chunks)]
 #![cfg_attr(stage0, feature(atomic_nand))]