diff options
| -rw-r--r-- | src/libcore/iter/adapters/mod.rs | 20 |
1 files changed, 7 insertions, 13 deletions
diff --git a/src/libcore/iter/adapters/mod.rs b/src/libcore/iter/adapters/mod.rs index 5787b9174ed..df824dd493e 100644 --- a/src/libcore/iter/adapters/mod.rs +++ b/src/libcore/iter/adapters/mod.rs @@ -1801,17 +1801,15 @@ where #[inline] fn nth(&mut self, n: usize) -> Option<I::Item> { // Can't just add n + self.n due to overflow. - if self.n == 0 { - self.iter.nth(n) - } else { + if self.n > 0 { let to_skip = self.n; self.n = 0; // nth(n) skips n+1 if self.iter.nth(to_skip - 1).is_none() { return None; } - self.iter.nth(n) } + self.iter.nth(n) } #[inline] @@ -1827,17 +1825,13 @@ where #[inline] fn last(mut self) -> Option<I::Item> { - if self.n == 0 { - self.iter.last() - } else { - let next = self.next(); - if next.is_some() { - // recurse. n should be 0. - self.last().or(next) - } else { - None + if self.n > 0 { + // nth(n) skips n+1 + if self.iter.nth(self.n - 1).is_none() { + return None; } } + self.iter.last() } #[inline] |