Struct kul::datum::DatumRc

pub struct DatumRc<TT, ET>(pub Rc<RcDatum<TT, ET>>);

This wrapper allows the needed recursive type definition for Rc to be used as the Datum reference type.

Methods

impl<TT, ET> DatumRc<TT, ET>

pub fn new(val: RcDatum<TT, ET>) -> Self

Make an Rced Datum with value from the given argument.

Trait Implementations

impl<TT, ET> Algo1DatumRef for DatumRc<TT, ET>

This allows using the custom drop algorithm, and it allows the algorithm to restructure tree nodes that have other weak references to them (which isn't possible with DerefTryMut::get_mut alone).

fn try_replace(
    this: &mut Self,
    val: Self::Target
) -> Result<Self::Target, Self::Target>

Returns the inner Datum and replaces it with the given value, if possible. Otherwise, an error is returned containing the passed-in value. Some implementations might always succeed.

fn set(this: &mut Self, val: Self::Target)

Mutates the inner Datum to be the given value. This must never fail. It is only called after our try_replace function is called on the same this value and succeeded, which allows this set function to never fail.

impl<TT, ET> RcLike for DatumRc<TT, ET>

type RC = Rc<RcDatum<TT, ET>>

The underlying Rc-like type

fn get_rc(this: &mut Self) -> &mut Self::RC

Return a mutable reference to this's underlying Rc-like value.

fn new_rc(val: Self::Target) -> Self::RC

Allocate a new Rc-like value and set its underlying value to the given val.

fn try_unwrap(rc: Self::RC) -> Result<Self::Target, Self::RC>

Do try_unwrap on the underlying Rc-like value.

fn try_replace(
    this: &mut Self,
    val: Self::Target
) -> Result<Self::Target, Self::Target>

Implementation of Algo1DatumRef::try_replace for generic Rc-like types. The default implementation uses try_unwrap and heap allocation which is inefficient.

fn set(this: &mut Self, val: Self::Target)

Implementation of Algo1DatumRef::set for generic Rc-like types. The default implementation uses DerefTryMut and is safe to call after a success-return from Algo1DatumRef::try_replace.

impl<TT, ET> RcLikeAtomicCounts for DatumRc<TT, ET>

fn counts(this: &Self) -> (usize, usize)

This is atomic enough to meet the requirements, because Rc is single-threaded.

fn try_replace_optim(
    this: &mut Self,
    val: Self::Target
) -> Result<Self::Target, Self::Target>

Optimized implementation of Algo1DatumRef::try_replace for generic Rc-like types that can supply both strong and weak reference counts atomically. The default implementation uses DerefTryMut when possible to avoid the heap allocation and unwrapping that the basic default RcLike::try_replace does.

impl<TT, ET> Drop for DatumRc<TT, ET>

Use algorithm #1 for dropping, to avoid extensive drop recursion.

fn drop(&mut self)

Executes the destructor for this type.

impl<TT: PartialEq, ET: PartialEq> PartialEq<DatumRc<TT, ET>> for DatumRc<TT, ET>

fn eq(&self, other: &DatumRc<TT, ET>) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &DatumRc<TT, ET>) -> bool

This method tests for !=.

impl<TT: Clone, ET: Clone> Clone for DatumRc<TT, ET>

fn clone(&self) -> DatumRc<TT, ET>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<TT: Eq, ET: Eq> Eq for DatumRc<TT, ET>

impl<TT: Debug, ET: Debug> Debug for DatumRc<TT, ET>

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<TT: Hash, ET: Hash> Hash for DatumRc<TT, ET>

fn hash<__HTTET: Hasher>(&self, state: &mut __HTTET)

Feeds this value into the given [Hasher].

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given [Hasher].

impl<TT, ET> Deref for DatumRc<TT, ET>

Required by DerefTryMut.

type Target = RcDatum<TT, ET>

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<TT, ET> DerefTryMut for DatumRc<TT, ET>

This allows Rc to be used as the Datum reference type.

fn get_mut(this: &mut Self) -> Option<&mut Self::Target>

Returns a mutable reference to the inner Datum if it can. Otherwise, returns None. Some implementations may never return None (e.g. for types that also implement DerefMut).