Use unsafe more idiomatically

Generally, including everything that makes an unsafe block safe in the
block is good style. Since the assert! is what makes this safe, it
should go inside the block. I also added a few bits of whitespace.

diff --git a/src/libcore/slice.rs b/src/libcore/slice.rs
index cf605f507bca66db2b25854e0cae188f17cea6f5..b5d3129d2683e6cc2fb54405efacd53d5664f048 100644 (file)
--- a/src/libcore/slice.rs
+++ b/src/libcore/slice.rs
@@ -303,8 +303,10 @@ fn get_mut(&mut self, index: usize) -> Option<&mut T> {
     fn split_at_mut(&mut self, mid: usize) -> (&mut [T], &mut [T]) {
         let len = self.len();
         let ptr = self.as_mut_ptr();
-        assert!(mid <= len);
+
         unsafe {
+            assert!(mid <= len);
+
             (from_raw_parts_mut(ptr, mid),
              from_raw_parts_mut(ptr.offset(mid as isize), len - mid))
         }