diff options
| -rw-r--r-- | src/libcore/iter/mod.rs | 52 | ||||
| -rw-r--r-- | src/test/run-pass/variance-iterators-in-libcore.rs | 17 |
2 files changed, 31 insertions, 38 deletions
diff --git a/src/libcore/iter/mod.rs b/src/libcore/iter/mod.rs index b1d3ab1d1fe..dd57fd1b519 100644 --- a/src/libcore/iter/mod.rs +++ b/src/libcore/iter/mod.rs @@ -643,7 +643,9 @@ impl<A, B> FusedIterator for Chain<A, B> pub struct Zip<A, B> { a: A, b: B, - spec: <(A, B) as ZipImplData>::Data, + // index and len are only used by the specialized version of zip + index: usize, + len: usize, } #[stable(feature = "rust1", since = "1.0.0")] @@ -685,17 +687,6 @@ trait ZipImpl<A, B> { B: DoubleEndedIterator + ExactSizeIterator; } -// Zip specialization data members -#[doc(hidden)] -trait ZipImplData { - type Data: 'static + Clone + Default + fmt::Debug; -} - -#[doc(hidden)] -impl<T> ZipImplData for T { - default type Data = (); -} - // General Zip impl #[doc(hidden)] impl<A, B> ZipImpl<A, B> for Zip<A, B> @@ -706,7 +697,8 @@ impl<A, B> ZipImpl<A, B> for Zip<A, B> Zip { a: a, b: b, - spec: Default::default(), // unused + index: 0, // unused + len: 0, // unused } } @@ -760,20 +752,6 @@ impl<A, B> ZipImpl<A, B> for Zip<A, B> } #[doc(hidden)] -#[derive(Default, Debug, Clone)] -struct ZipImplFields { - index: usize, - len: usize, -} - -#[doc(hidden)] -impl<A, B> ZipImplData for (A, B) - where A: TrustedRandomAccess, B: TrustedRandomAccess -{ - type Data = ZipImplFields; -} - -#[doc(hidden)] impl<A, B> ZipImpl<A, B> for Zip<A, B> where A: TrustedRandomAccess, B: TrustedRandomAccess { @@ -782,18 +760,16 @@ impl<A, B> ZipImpl<A, B> for Zip<A, B> Zip { a: a, b: b, - spec: ZipImplFields { - index: 0, - len: len, - } + index: 0, + len: len, } } #[inline] fn next(&mut self) -> Option<(A::Item, B::Item)> { - if self.spec.index < self.spec.len { - let i = self.spec.index; - self.spec.index += 1; + if self.index < self.len { + let i = self.index; + self.index += 1; unsafe { Some((self.a.get_unchecked(i), self.b.get_unchecked(i))) } @@ -804,7 +780,7 @@ impl<A, B> ZipImpl<A, B> for Zip<A, B> #[inline] fn size_hint(&self) -> (usize, Option<usize>) { - let len = self.spec.len - self.spec.index; + let len = self.len - self.index; (len, Some(len)) } @@ -813,9 +789,9 @@ impl<A, B> ZipImpl<A, B> for Zip<A, B> where A: DoubleEndedIterator + ExactSizeIterator, B: DoubleEndedIterator + ExactSizeIterator { - if self.spec.index < self.spec.len { - self.spec.len -= 1; - let i = self.spec.len; + if self.index < self.len { + self.len -= 1; + let i = self.len; unsafe { Some((self.a.get_unchecked(i), self.b.get_unchecked(i))) } diff --git a/src/test/run-pass/variance-iterators-in-libcore.rs b/src/test/run-pass/variance-iterators-in-libcore.rs new file mode 100644 index 00000000000..b9677d5ba85 --- /dev/null +++ b/src/test/run-pass/variance-iterators-in-libcore.rs @@ -0,0 +1,17 @@ +// Copyright 2015 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. + +#![allow(warnings)] + +use std::iter::Zip; + +fn zip_covariant<'a, A, B>(iter: Zip<&'static A, &'static B>) -> Zip<&'a A, &'a B> { iter } + +fn main() { } |