From c98f0cb3627fbdc2f1e56cfe1aad20a96730d208 Mon Sep 17 00:00:00 2001
From: Daniel Micay <danielmicay@gmail.com>
Date: Wed, 17 Apr 2013 19:34:53 -0400
Subject: [PATCH] vec: add an external iterator
---
src/libcore/vec.rs | 55 +++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 54 insertions(+), 1 deletion(-)
diff --git a/src/libcore/vec.rs b/src/libcore/vec.rs
index 30201304d6191..0403ae64f0205 100644
--- a/src/libcore/vec.rs
+++ b/src/libcore/vec.rs
@@ -18,6 +18,10 @@ use cmp::{Eq, Ord, TotalEq, TotalOrd, Ordering, Less, Equal, Greater};
use clone::Clone;
use iter::BaseIter;
use iter;
+#[cfg(stage1)]
+#[cfg(stage2)]
+#[cfg(stage3)]
+use iterator::Iterator;
use kinds::Copy;
use libc;
use option::{None, Option, Some};
@@ -1919,6 +1923,7 @@ impl<'self,T> ImmutableVector<T> for &'self [T] {
#[cfg(stage3)]
pub trait ImmutableVector<'self, T> {
fn slice(&self, start: uint, end: uint) -> &'self [T];
+ fn iter(self) -> VecIterator<'self, T>;
fn head(&self) -> &'self T;
fn head_opt(&self) -> Option<&'self T>;
fn tail(&self) -> &'self [T];
@@ -1949,6 +1954,15 @@ impl<'self,T> ImmutableVector<'self, T> for &'self [T] {
slice(*self, start, end)
}
+ #[inline]
+ fn iter(self) -> VecIterator<'self, T> {
+ unsafe {
+ let p = vec::raw::to_ptr(self);
+ VecIterator{ptr: p, end: p.offset(self.len()),
+ lifetime: cast::transmute(p)}
+ }
+ }
+
/// Returns the first element of a vector, failing if the vector is empty.
#[inline]
fn head(&self) -> &'self T { head(*self) }
@@ -2795,7 +2809,33 @@ impl<A:Clone> Clone for ~[A] {
}
}
-// ___________________________________________________________________________
+// could be implemented with &[T] with .slice(), but this avoids bounds checks
+#[cfg(stage1)]
+#[cfg(stage2)]
+#[cfg(stage3)]
+pub struct VecIterator<'self, T> {
+ priv ptr: *T,
+ priv end: *T,
+ priv lifetime: &'self T // FIXME: #5922
+}
+
+#[cfg(stage1)]
+#[cfg(stage2)]
+#[cfg(stage3)]
+impl<'self, T> Iterator<&'self T> for VecIterator<'self, T> {
+ #[inline]
+ fn next(&mut self) -> Option<&'self T> {
+ unsafe {
+ if self.ptr == self.end {
+ None
+ } else {
+ let old = self.ptr;
+ self.ptr = self.ptr.offset(1);
+ Some(cast::transmute(old))
+ }
+ }
+ }
+}
#[cfg(test)]
mod tests {
@@ -4421,6 +4461,19 @@ mod tests {
[1, 2, 3, 4, 5, 5, 5, 5].cmp(& &[1, 2, 3, 4, 5, 6]) == Less;
[2, 2].cmp(& &[1, 2, 3, 4]) == Greater;
}
+
+ #[test]
+ fn test_iterator() {
+ use iterator::*;
+ let xs = [1, 2, 5, 10, 11];
+ let ys = [1, 2, 5, 10, 11, 19];
+ let mut it = xs.iter();
+ let mut i = 0;
+ for it.advance |&x| {
+ assert_eq!(x, ys[i]);
+ i += 1;
+ }
+ }
}
// Local Variables: