18 files changed, 60 insertions, 60 deletions

diff --git a/src/libcore/alloc.rs b/src/libcore/alloc.rs
index 66a3094d77d..f49e226a5cb 100644
--- a/src/libcore/alloc.rs
+++ b/src/libcore/alloc.rs
@@ -425,7 +425,7 @@ impl fmt::Display for CannotReallocInPlace {
 /// The `GlobalAlloc` trait is an `unsafe` trait for a number of reasons, and
 /// implementors must ensure that they adhere to these contracts:
 ///
-/// * It's undefined behavior if global allocators unwind.  This restriction may
+/// * It's undefined behavior if global allocators unwind. This restriction may
 ///   be lifted in the future, but currently a panic from any of these
 ///   functions may lead to memory unsafety.
 ///
diff --git a/src/libcore/any.rs b/src/libcore/any.rs
index 2afd9e0c072..01ab523a4c3 100644
--- a/src/libcore/any.rs
+++ b/src/libcore/any.rs
@@ -18,7 +18,7 @@
 //!
 //! Consider a situation where we want to log out a value passed to a function.
 //! We know the value we're working on implements Debug, but we don't know its
-//! concrete type.  We want to give special treatment to certain types: in this
+//! concrete type. We want to give special treatment to certain types: in this
 //! case printing out the length of String values prior to their value.
 //! We don't know the concrete type of our value at compile time, so we need to
 //! use runtime reflection instead.
@@ -31,8 +31,8 @@
 //! fn log<T: Any + Debug>(value: &T) {
 //!     let value_any = value as &dyn Any;
 //!
-//!     // try to convert our value to a String.  If successful, we want to
-//!     // output the String's length as well as its value.  If not, it's a
+//!     // Try to convert our value to a `String`. If successful, we want to
+//!     // output the String`'s length as well as its value. If not, it's a
 //!     // different type: just print it out unadorned.
 //!     match value_any.downcast_ref::<String>() {
 //!         Some(as_string) => {
diff --git a/src/libcore/cell.rs b/src/libcore/cell.rs
index d57ca13a334..fb8d7e5d088 100644
--- a/src/libcore/cell.rs
+++ b/src/libcore/cell.rs
@@ -1133,7 +1133,7 @@ impl<'b, T: ?Sized> Ref<'b, T> {
     /// The `RefCell` is already immutably borrowed, so this cannot fail.
     ///
     /// This is an associated function that needs to be used as
-    /// `Ref::clone(...)`.  A `Clone` implementation or a method would interfere
+    /// `Ref::clone(...)`. A `Clone` implementation or a method would interfere
     /// with the widespread use of `r.borrow().clone()` to clone the contents of
     /// a `RefCell`.
     #[stable(feature = "cell_extras", since = "1.15.0")]
@@ -1174,7 +1174,7 @@ impl<'b, T: ?Sized> Ref<'b, T> {
         }
     }
 
-    /// Split a `Ref` into multiple `Ref`s for different components of the
+    /// Splits a `Ref` into multiple `Ref`s for different components of the
     /// borrowed data.
     ///
     /// The `RefCell` is already immutably borrowed, so this cannot fail.
@@ -1223,7 +1223,7 @@ impl<'b, T: ?Sized> RefMut<'b, T> {
     /// The `RefCell` is already mutably borrowed, so this cannot fail.
     ///
     /// This is an associated function that needs to be used as
-    /// `RefMut::map(...)`.  A method would interfere with methods of the same
+    /// `RefMut::map(...)`. A method would interfere with methods of the same
     /// name on the contents of a `RefCell` used through `Deref`.
     ///
     /// # Examples
@@ -1253,7 +1253,7 @@ impl<'b, T: ?Sized> RefMut<'b, T> {
         }
     }
 
-    /// Split a `RefMut` into multiple `RefMut`s for different components of the
+    /// Splits a `RefMut` into multiple `RefMut`s for different components of the
     /// borrowed data.
     ///
     /// The underlying `RefCell` will remain mutably borrowed until both
diff --git a/src/libcore/cmp.rs b/src/libcore/cmp.rs
index d43a5c1032c..81fcdeee12d 100644
--- a/src/libcore/cmp.rs
+++ b/src/libcore/cmp.rs
@@ -26,7 +26,7 @@ use self::Ordering::*;
 /// relations](http://en.wikipedia.org/wiki/Partial_equivalence_relation).
 ///
 /// This trait allows for partial equality, for types that do not have a full
-/// equivalence relation.  For example, in floating point numbers `NaN != NaN`,
+/// equivalence relation. For example, in floating point numbers `NaN != NaN`,
 /// so floating point types implement `PartialEq` but not `Eq`.
 ///
 /// Formally, the equality must be (for all `a`, `b` and `c`):
diff --git a/src/libcore/convert.rs b/src/libcore/convert.rs
index 203be541e49..de34e79f597 100644
--- a/src/libcore/convert.rs
+++ b/src/libcore/convert.rs
@@ -217,7 +217,7 @@ pub trait AsMut<T: ?Sized> {
 ///
 /// There is one exception to implementing `Into`, and it's kind of esoteric.
 /// If the destination type is not part of the current crate, and it uses a
-/// generic variable, then you can't implement `From` directly.  For example,
+/// generic variable, then you can't implement `From` directly. For example,
 /// take this crate:
 ///
 /// ```compile_fail
diff --git a/src/libcore/intrinsics.rs b/src/libcore/intrinsics.rs
index e927ed40d7f..c29358c4c4a 100644
--- a/src/libcore/intrinsics.rs
+++ b/src/libcore/intrinsics.rs
@@ -1,6 +1,6 @@
-//! rustc compiler intrinsics.
+//! Compiler intrinsics.
 //!
-//! The corresponding definitions are in librustc_codegen_llvm/intrinsic.rs.
+//! The corresponding definitions are in `librustc_codegen_llvm/intrinsic.rs`.
 //!
 //! # Volatiles
 //!
@@ -697,7 +697,7 @@ extern "rust-intrinsic" {
     /// Creates a value initialized to zero.
     ///
     /// `init` is unsafe because it returns a zeroed-out datum,
-    /// which is unsafe unless T is `Copy`.  Also, even if T is
+    /// which is unsafe unless `T` is `Copy`. Also, even if T is
     /// `Copy`, an all-zero value may not correspond to any legitimate
     /// state for the type in question.
     pub fn init<T>() -> T;
@@ -988,7 +988,7 @@ extern "rust-intrinsic" {
     ///   beginning at `dst` with the same size.
     ///
     /// Like [`read`], `copy_nonoverlapping` creates a bitwise copy of `T`, regardless of
-    /// whether `T` is [`Copy`].  If `T` is not [`Copy`], using *both* the values
+    /// whether `T` is [`Copy`]. If `T` is not [`Copy`], using *both* the values
     /// in the region beginning at `*src` and the region beginning at `*dst` can
     /// [violate memory safety][read-ownership].
     ///
@@ -1055,7 +1055,7 @@ extern "rust-intrinsic" {
     /// [`copy_nonoverlapping`] can be used instead.
     ///
     /// `copy` is semantically equivalent to C's [`memmove`], but with the argument
-    /// order swapped.  Copying takes place as if the bytes were copied from `src`
+    /// order swapped. Copying takes place as if the bytes were copied from `src`
     /// to a temporary array and then copied from the array to `dst`.
     ///
     /// [`copy_nonoverlapping`]: ./fn.copy_nonoverlapping.html
@@ -1072,7 +1072,7 @@ extern "rust-intrinsic" {
     /// * Both `src` and `dst` must be properly aligned.
     ///
     /// Like [`read`], `copy` creates a bitwise copy of `T`, regardless of
-    /// whether `T` is [`Copy`].  If `T` is not [`Copy`], using both the values
+    /// whether `T` is [`Copy`]. If `T` is not [`Copy`], using both the values
     /// in the region beginning at `*src` and the region beginning at `*dst` can
     /// [violate memory safety][read-ownership].
     ///
diff --git a/src/libcore/iter/traits/iterator.rs b/src/libcore/iter/traits/iterator.rs
index 218c7199f35..1c86745d9ba 100644
--- a/src/libcore/iter/traits/iterator.rs
+++ b/src/libcore/iter/traits/iterator.rs
@@ -564,9 +564,9 @@ pub trait Iterator {
     /// Calls a closure on each element of an iterator.
     ///
     /// This is equivalent to using a [`for`] loop on the iterator, although
-    /// `break` and `continue` are not possible from a closure.  It's generally
+    /// `break` and `continue` are not possible from a closure. It's generally
     /// more idiomatic to use a `for` loop, but `for_each` may be more legible
-    /// when processing items at the end of longer iterator chains.  In some
+    /// when processing items at the end of longer iterator chains. In some
     /// cases `for_each` may also be faster than a loop, because it will use
     /// internal iteration on adaptors like `Chain`.
     ///
@@ -1515,7 +1515,7 @@ pub trait Iterator {
     /// is propagated back to the caller immediately (short-circuiting).
     ///
     /// The initial value is the value the accumulator will have on the first
-    /// call.  If applying the closure succeeded against every element of the
+    /// call. If applying the closure succeeded against every element of the
     /// iterator, `try_fold()` returns the final accumulator as success.
     ///
     /// Folding is useful whenever you have a collection of something, and want
@@ -1528,10 +1528,10 @@ pub trait Iterator {
     /// do something better than the default `for` loop implementation.
     ///
     /// In particular, try to have this call `try_fold()` on the internal parts
-    /// from which this iterator is composed.  If multiple calls are needed,
+    /// from which this iterator is composed. If multiple calls are needed,
     /// the `?` operator may be convenient for chaining the accumulator value
     /// along, but beware any invariants that need to be upheld before those
-    /// early returns.  This is a `&mut self` method, so iteration needs to be
+    /// early returns. This is a `&mut self` method, so iteration needs to be
     /// resumable after hitting an error here.
     ///
     /// # Examples
diff --git a/src/libcore/macros.rs b/src/libcore/macros.rs
index 664490c1997..d81d309a81a 100644
--- a/src/libcore/macros.rs
+++ b/src/libcore/macros.rs
@@ -432,7 +432,7 @@ macro_rules! writeln {
 /// * Iterators that dynamically terminate.
 ///
 /// If the determination that the code is unreachable proves incorrect, the
-/// program immediately terminates with a [`panic!`].  The function [`unreachable_unchecked`],
+/// program immediately terminates with a [`panic!`]. The function [`unreachable_unchecked`],
 /// which belongs to the [`std::hint`] module, informs the compiler to
 /// optimize the code out of the release version entirely.
 ///
diff --git a/src/libcore/mem.rs b/src/libcore/mem.rs
index 2f86e13b938..855b8ba7f96 100644
--- a/src/libcore/mem.rs
+++ b/src/libcore/mem.rs
@@ -1101,7 +1101,7 @@ impl<T> MaybeUninit<T> {
     }
 
     /// Create a new `MaybeUninit` in an uninitialized state, with the memory being
-    /// filled with `0` bytes.  It depends on `T` whether that already makes for
+    /// filled with `0` bytes. It depends on `T` whether that already makes for
     /// proper initialization. For example, `MaybeUninit<usize>::zeroed()` is initialized,
     /// but `MaybeUninit<&'static i32>::zeroed()` is not because references must not
     /// be null.
@@ -1130,7 +1130,7 @@ impl<T> MaybeUninit<T> {
         }
     }
 
-    /// Extract the value from the `MaybeUninit` container.  This is a great way
+    /// Extract the value from the `MaybeUninit` container. This is a great way
     /// to ensure that the data will get dropped, because the resulting `T` is
     /// subject to the usual drop handling.
     ///
diff --git a/src/libcore/num/dec2flt/mod.rs b/src/libcore/num/dec2flt/mod.rs
index 14a912872be..a1bf6f824f6 100644
--- a/src/libcore/num/dec2flt/mod.rs
+++ b/src/libcore/num/dec2flt/mod.rs
@@ -37,7 +37,7 @@
 //!
 //! In addition, there are numerous helper functions that are used in the paper but not available
 //! in Rust (or at least in core). Our version is additionally complicated by the need to handle
-//! overflow and underflow and the desire to handle subnormal numbers.  Bellerophon and
+//! overflow and underflow and the desire to handle subnormal numbers. Bellerophon and
 //! Algorithm R have trouble with overflow, subnormals, and underflow. We conservatively switch to
 //! Algorithm M (with the modifications described in section 8 of the paper) well before the
 //! inputs get into the critical region.
@@ -148,7 +148,7 @@ macro_rules! from_str_float_impl {
             /// # Return value
             ///
             /// `Err(ParseFloatError)` if the string did not represent a valid
-            /// number.  Otherwise, `Ok(n)` where `n` is the floating-point
+            /// number. Otherwise, `Ok(n)` where `n` is the floating-point
             /// number represented by `src`.
             #[inline]
             fn from_str(src: &str) -> Result<Self, ParseFloatError> {
@@ -209,7 +209,7 @@ fn pfe_invalid() -> ParseFloatError {
     ParseFloatError { kind: FloatErrorKind::Invalid }
 }
 
-/// Split decimal string into sign and the rest, without inspecting or validating the rest.
+/// Splits a decimal string into sign and the rest, without inspecting or validating the rest.
 fn extract_sign(s: &str) -> (Sign, &str) {
     match s.as_bytes()[0] {
         b'+' => (Sign::Positive, &s[1..]),
diff --git a/src/libcore/num/dec2flt/rawfp.rs b/src/libcore/num/dec2flt/rawfp.rs
index 6976bd1a0ee..06d7fb8d103 100644
--- a/src/libcore/num/dec2flt/rawfp.rs
+++ b/src/libcore/num/dec2flt/rawfp.rs
@@ -59,10 +59,10 @@ pub trait RawFloat
     /// Type used by `to_bits` and `from_bits`.
     type Bits: Add<Output = Self::Bits> + From<u8> + TryFrom<u64>;
 
-    /// Raw transmutation to integer.
+    /// Performs a raw transmutation to an integer.
     fn to_bits(self) -> Self::Bits;
 
-    /// Raw transmutation from integer.
+    /// Performs a raw transmutation from an integer.
     fn from_bits(v: Self::Bits) -> Self;
 
     /// Returns the category that this number falls into.
@@ -71,14 +71,14 @@ pub trait RawFloat
     /// Returns the mantissa, exponent and sign as integers.
     fn integer_decode(self) -> (u64, i16, i8);
 
-    /// Decode the float.
+    /// Decodes the float.
     fn unpack(self) -> Unpacked;
 
-    /// Cast from a small integer that can be represented exactly.  Panic if the integer can't be
+    /// Casts from a small integer that can be represented exactly. Panic if the integer can't be
     /// represented, the other code in this module makes sure to never let that happen.
     fn from_int(x: u64) -> Self;
 
-    /// Get the value 10<sup>e</sup> from a pre-computed table.
+    /// Gets the value 10<sup>e</sup> from a pre-computed table.
     /// Panics for `e >= CEIL_LOG5_OF_MAX_SIG`.
     fn short_fast_pow10(e: usize) -> Self;
 
diff --git a/src/libcore/ops/arith.rs b/src/libcore/ops/arith.rs
index 7d8bf18d33a..202beddfcb0 100644
--- a/src/libcore/ops/arith.rs
+++ b/src/libcore/ops/arith.rs
@@ -518,7 +518,7 @@ pub trait Rem<RHS=Self> {
 
 macro_rules! rem_impl_integer {
     ($($t:ty)*) => ($(
-        /// This operation satisfies `n % d == n - (n / d) * d`.  The
+        /// This operation satisfies `n % d == n - (n / d) * d`. The
         /// result has the same sign as the left operand.
         #[stable(feature = "rust1", since = "1.0.0")]
         impl Rem for $t {
diff --git a/src/libcore/ops/try.rs b/src/libcore/ops/try.rs
index 380bd12131c..9fa2c81954e 100644
--- a/src/libcore/ops/try.rs
+++ b/src/libcore/ops/try.rs
@@ -1,7 +1,7 @@
 /// A trait for customizing the behavior of the `?` operator.
 ///
 /// A type implementing `Try` is one that has a canonical way to view it
-/// in terms of a success/failure dichotomy.  This trait allows both
+/// in terms of a success/failure dichotomy. This trait allows both
 /// extracting those success or failure values from an existing instance and
 /// creating a new instance from a success or failure value.
 #[unstable(feature = "try_trait", issue = "42327")]
diff --git a/src/libcore/ptr.rs b/src/libcore/ptr.rs
index 537aa92c2cf..20960845718 100644
--- a/src/libcore/ptr.rs
+++ b/src/libcore/ptr.rs
@@ -12,7 +12,7 @@
 //! to access only a single value, in which case the documentation omits the size
 //! and implicitly assumes it to be `size_of::<T>()` bytes.
 //!
-//! The precise rules for validity are not determined yet.  The guarantees that are
+//! The precise rules for validity are not determined yet. The guarantees that are
 //! provided at this point are very minimal:
 //!
 //! * A [null] pointer is *never* valid, not even for accesses of [size zero][zst].
@@ -104,7 +104,7 @@ pub use intrinsics::write_bytes;
 ///
 /// * `to_drop` must be [valid] for reads.
 ///
-/// * `to_drop` must be properly aligned.  See the example below for how to drop
+/// * `to_drop` must be properly aligned. See the example below for how to drop
 ///   an unaligned pointer.
 ///
 /// Additionally, if `T` is not [`Copy`], using the pointed-to value after
@@ -135,7 +135,7 @@ pub use intrinsics::write_bytes;
 /// unsafe {
 ///     // Get a raw pointer to the last element in `v`.
 ///     let ptr = &mut v[1] as *mut _;
-///     // Shorten `v` to prevent the last item from being dropped.  We do that first,
+///     // Shorten `v` to prevent the last item from being dropped. We do that first,
 ///     // to prevent issues if the `drop_in_place` below panics.
 ///     v.set_len(1);
 ///     // Without a call `drop_in_place`, the last item would never be dropped,
@@ -531,7 +531,7 @@ pub unsafe fn replace<T>(dst: *mut T, mut src: T) -> T {
 ///
 /// `read` creates a bitwise copy of `T`, regardless of whether `T` is [`Copy`].
 /// If `T` is not [`Copy`], using both the returned value and the value at
-/// `*src` can violate memory safety.  Note that assigning to `*src` counts as a
+/// `*src` can violate memory safety. Note that assigning to `*src` counts as a
 /// use because it will attempt to drop the value at `*src`.
 ///
 /// [`write`] can be used to overwrite data without causing it to be dropped.
@@ -588,7 +588,7 @@ pub unsafe fn read<T>(src: *const T) -> T {
 /// * `src` must be [valid] for reads.
 ///
 /// Like [`read`], `read_unaligned` creates a bitwise copy of `T`, regardless of
-/// whether `T` is [`Copy`].  If `T` is not [`Copy`], using both the returned
+/// whether `T` is [`Copy`]. If `T` is not [`Copy`], using both the returned
 /// value and the value at `*src` can [violate memory safety][read-ownership].
 ///
 /// Note that even if `T` has size `0`, the pointer must be non-NULL.
@@ -839,7 +839,7 @@ pub unsafe fn write_unaligned<T>(dst: *mut T, src: T) {
 /// * `src` must be properly aligned.
 ///
 /// Like [`read`], `read_unaligned` creates a bitwise copy of `T`, regardless of
-/// whether `T` is [`Copy`].  If `T` is not [`Copy`], using both the returned
+/// whether `T` is [`Copy`]. If `T` is not [`Copy`], using both the returned
 /// value and the value at `*src` can [violate memory safety][read-ownership].
 /// However, storing non-[`Copy`] types in volatile memory is almost certainly
 /// incorrect.
@@ -1093,7 +1093,7 @@ impl<T: ?Sized> *const T {
     /// unless `x` and `y` point into the same allocated object.
     ///
     /// Always use `.offset(count)` instead when possible, because `offset`
-    /// allows the compiler to optimize better.  If you need to cross object
+    /// allows the compiler to optimize better. If you need to cross object
     /// boundaries, cast the pointer to an integer and do the arithmetic there.
     ///
     /// # Examples
@@ -1712,7 +1712,7 @@ impl<T: ?Sized> *mut T {
     /// unless `x` and `y` point into the same allocated object.
     ///
     /// Always use `.offset(count)` instead when possible, because `offset`
-    /// allows the compiler to optimize better.  If you need to cross object
+    /// allows the compiler to optimize better. If you need to cross object
     /// boundaries, cast the pointer to an integer and do the arithmetic there.
     ///
     /// # Examples
diff --git a/src/libcore/slice/mod.rs b/src/libcore/slice/mod.rs
index d062da0c247..e2129c68e7f 100644
--- a/src/libcore/slice/mod.rs
+++ b/src/libcore/slice/mod.rs
@@ -1197,7 +1197,7 @@ impl<T> [T] {
 
     /// Returns an iterator over subslices separated by elements that match
     /// `pred` limited to returning at most `n` items. This starts at the end of
-    /// the slice and works backwards.  The matched element is not contained in
+    /// the slice and works backwards. The matched element is not contained in
     /// the subslices.
     ///
     /// The last element returned, if any, will contain the remainder of the
@@ -3145,7 +3145,7 @@ unsafe impl<T: Sync> Sync for Iter<'_, T> {}
 unsafe impl<T: Sync> Send for Iter<'_, T> {}
 
 impl<'a, T> Iter<'a, T> {
-    /// View the underlying data as a subslice of the original data.
+    /// Views the underlying data as a subslice of the original data.
     ///
     /// This has the same lifetime as the original slice, and so the
     /// iterator can continue to be used while this exists.
@@ -3247,7 +3247,7 @@ unsafe impl<T: Sync> Sync for IterMut<'_, T> {}
 unsafe impl<T: Send> Send for IterMut<'_, T> {}
 
 impl<'a, T> IterMut<'a, T> {
-    /// View the underlying data as a subslice of the original data.
+    /// Views the underlying data as a subslice of the original data.
     ///
     /// To avoid creating `&mut` references that alias, this is forced
     /// to consume the iterator.
diff --git a/src/libcore/slice/rotate.rs b/src/libcore/slice/rotate.rs
index 52677713f5a..9b35b51349a 100644
--- a/src/libcore/slice/rotate.rs
+++ b/src/libcore/slice/rotate.rs
@@ -26,7 +26,7 @@ impl<T> RawArray<T> {
 }
 
 /// Rotates the range `[mid-left, mid+right)` such that the element at `mid`
-/// becomes the first element.  Equivalently, rotates the range `left`
+/// becomes the first element. Equivalently, rotates the range `left`
 /// elements to the left or `right` elements to the right.
 ///
 /// # Safety
@@ -36,10 +36,10 @@ impl<T> RawArray<T> {
 /// # Algorithm
 ///
 /// For longer rotations, swap the left-most `delta = min(left, right)`
-/// elements with the right-most `delta` elements.  LLVM vectorizes this,
+/// elements with the right-most `delta` elements. LLVM vectorizes this,
 /// which is profitable as we only reach this step for a "large enough"
-/// rotation.  Doing this puts `delta` elements on the larger side into the
-/// correct position, leaving a smaller rotate problem.  Demonstration:
+/// rotation. Doing this puts `delta` elements on the larger side into the
+/// correct position, leaving a smaller rotate problem. Demonstration:
 ///
 /// ```text
 /// [ 6 7 8 9 10 11 12 13 . 1 2 3 4 5 ]
diff --git a/src/libcore/str/mod.rs b/src/libcore/str/mod.rs
index 81c351be305..c43db916888 100644
--- a/src/libcore/str/mod.rs
+++ b/src/libcore/str/mod.rs
@@ -612,7 +612,7 @@ impl<'a> DoubleEndedIterator for Chars<'a> {
 impl FusedIterator for Chars<'_> {}
 
 impl<'a> Chars<'a> {
-    /// View the underlying data as a subslice of the original data.
+    /// Views the underlying data as a subslice of the original data.
     ///
     /// This has the same lifetime as the original slice, and so the
     /// iterator can continue to be used while this exists.
@@ -702,7 +702,7 @@ impl<'a> DoubleEndedIterator for CharIndices<'a> {
 impl FusedIterator for CharIndices<'_> {}
 
 impl<'a> CharIndices<'a> {
-    /// View the underlying data as a subslice of the original data.
+    /// Views the underlying data as a subslice of the original data.
     ///
     /// This has the same lifetime as the original slice, and so the
     /// iterator can continue to be used while this exists.
@@ -1579,9 +1579,9 @@ mod traits {
 
     /// Implements ordering of strings.
     ///
-    /// Strings are ordered  lexicographically by their byte values.  This orders Unicode code
-    /// points based on their positions in the code charts.  This is not necessarily the same as
-    /// "alphabetical" order, which varies by language and locale.  Sorting strings according to
+    /// Strings are ordered  lexicographically by their byte values. This orders Unicode code
+    /// points based on their positions in the code charts. This is not necessarily the same as
+    /// "alphabetical" order, which varies by language and locale. Sorting strings according to
     /// culturally-accepted standards requires locale-specific data that is outside the scope of
     /// the `str` type.
     #[stable(feature = "rust1", since = "1.0.0")]
@@ -1607,9 +1607,9 @@ mod traits {
 
     /// Implements comparison operations on strings.
     ///
-    /// Strings are compared lexicographically by their byte values.  This compares Unicode code
-    /// points based on their positions in the code charts.  This is not necessarily the same as
-    /// "alphabetical" order, which varies by language and locale.  Comparing strings according to
+    /// Strings are compared lexicographically by their byte values. This compares Unicode code
+    /// points based on their positions in the code charts. This is not necessarily the same as
+    /// "alphabetical" order, which varies by language and locale. Comparing strings according to
     /// culturally-accepted standards requires locale-specific data that is outside the scope of
     /// the `str` type.
     #[stable(feature = "rust1", since = "1.0.0")]
@@ -2643,7 +2643,7 @@ impl str {
         Bytes(self.as_bytes().iter().cloned())
     }
 
-    /// Split a string slice by whitespace.
+    /// Splits a string slice by whitespace.
     ///
     /// The iterator returned will return string slices that are sub-slices of
     /// the original string slice, separated by any amount of whitespace.
@@ -2686,7 +2686,7 @@ impl str {
         SplitWhitespace { inner: self.split(IsWhitespace).filter(IsNotEmpty) }
     }
 
-    /// Split a string slice by ASCII whitespace.
+    /// Splits a string slice by ASCII whitespace.
     ///
     /// The iterator returned will return string slices that are sub-slices of
     /// the original string slice, separated by any amount of ASCII whitespace.
diff --git a/src/libcore/time.rs b/src/libcore/time.rs
index a751965dffa..ee583c829dd 100644
--- a/src/libcore/time.rs
+++ b/src/libcore/time.rs
@@ -43,7 +43,7 @@ pub const NANOSECOND: Duration = Duration::from_nanos(1);
 /// timeouts.
 ///
 /// Each `Duration` is composed of a whole number of seconds and a fractional part
-/// represented in nanoseconds.  If the underlying system does not support
+/// represented in nanoseconds. If the underlying system does not support
 /// nanosecond-level precision, APIs binding a system timeout will typically round up
 /// the number of nanoseconds.
 ///