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Updates to src/libcore/ops.rs docs for RFC#1228 (Placement Left Arrow) #38930

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Jan 25, 2017
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Updates to src/libcore/ops.rs docs for RFC#1228 (Placement Left Arrow) #38930

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16 changes: 8 additions & 8 deletions src/libcore/ops.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -2747,7 +2747,7 @@ impl<T: ?Sized+Unsize<U>, U: ?Sized> CoerceUnsized<*const U> for *mut T {}
#[unstable(feature = "coerce_unsized", issue = "27732")]
impl<T: ?Sized+Unsize<U>, U: ?Sized> CoerceUnsized<*const U> for *const T {}

/// Both `in (PLACE) EXPR` and `box EXPR` desugar into expressions
/// Both `PLACE <- EXPR` and `box EXPR` desugar into expressions
/// that allocate an intermediate "place" that holds uninitialized
/// state. The desugaring evaluates EXPR, and writes the result at
/// the address returned by the `pointer` method of this trait.
Expand All @@ -2762,7 +2762,7 @@ impl<T: ?Sized+Unsize<U>, U: ?Sized> CoerceUnsized<*const U> for *const T {}
/// converting the agent to an instance of the owning pointer, via the
/// appropriate `finalize` method (see the `InPlace`.
///
/// If evaluating EXPR fails, then the destructor for the
/// If evaluating EXPR fails, then it is up to the destructor for the
/// implementation of Place to clean up any intermediate state
/// (e.g. deallocate box storage, pop a stack, etc).
#[unstable(feature = "placement_new_protocol", issue = "27779")]
Expand All @@ -2773,9 +2773,9 @@ pub trait Place<Data: ?Sized> {
fn pointer(&mut self) -> *mut Data;
}

/// Interface to implementations of `in (PLACE) EXPR`.
/// Interface to implementations of `PLACE <- EXPR`.
///
/// `in (PLACE) EXPR` effectively desugars into:
/// `PLACE <- EXPR` effectively desugars into:
///
/// ```rust,ignore
/// let p = PLACE;
Expand All @@ -2788,7 +2788,7 @@ pub trait Place<Data: ?Sized> {
/// }
/// ```
///
/// The type of `in (PLACE) EXPR` is derived from the type of `PLACE`;
/// The type of `PLACE <- EXPR` is derived from the type of `PLACE`;
/// if the type of `PLACE` is `P`, then the final type of the whole
/// expression is `P::Place::Owner` (see the `InPlace` and `Boxed`
/// traits).
Expand All @@ -2806,12 +2806,12 @@ pub trait Placer<Data: ?Sized> {
fn make_place(self) -> Self::Place;
}

/// Specialization of `Place` trait supporting `in (PLACE) EXPR`.
/// Specialization of `Place` trait supporting `PLACE <- EXPR`.
#[unstable(feature = "placement_new_protocol", issue = "27779")]
pub trait InPlace<Data: ?Sized>: Place<Data> {
/// `Owner` is the type of the end value of `in (PLACE) EXPR`
/// `Owner` is the type of the end value of `PLACE <- EXPR`
///
/// Note that when `in (PLACE) EXPR` is solely used for
/// Note that when `PLACE <- EXPR` is solely used for
/// side-effecting an existing data-structure,
/// e.g. `Vec::emplace_back`, then `Owner` need not carry any
/// information at all (e.g. it can be the unit type `()` in that
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