Enum VnodeCount

pub enum VnodeCount {
    Placeholder,
    Set(NonZeroUsize),
    CompatHash,
    CompatSingleton,
}

The different cases of maybe_vnode_count field in the protobuf message.

Variants

Placeholder

The field is a placeholder and has to be filled first before using it.

Set(NonZeroUsize)

The field is set to a specific value.

CompatHash

The field is unset because the table/fragment is persisted as hash-distributed in an older version.

CompatSingleton

The field is unset because the table/fragment is persisted as singleton in an older version.

Implementations

impl VnodeCount

pub fn set(v: impl TryInto<usize> + Copy + Debug) -> Self

Creates a VnodeCount set to the given value.

pub fn for_test() -> Self

Creates a VnodeCount set to the value for testing.

Equivalent to VnodeCount::set(VirtualNode::COUNT_FOR_TEST).

fn from_protobuf( v: Option<u32>, compat_is_singleton: impl FnOnce() -> bool, ) -> Self

Converts from protobuf representation of maybe_vnode_count. If the value is not set, call compat_is_singleton to determine whether it should be treated as a singleton when it comes to backward compatibility.

pub fn to_protobuf(self) -> Option<u32>

Converts to protobuf representation for maybe_vnode_count.

pub fn value_opt(self) -> Option<usize>

Returns the value of the vnode count, or None if it’s a placeholder.

pub fn value(self) -> usize

Returns the value of the vnode count. Panics if it’s a placeholder.

Trait Implementations

impl Clone for VnodeCount

fn clone(&self) -> VnodeCount

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for VnodeCount

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

Formats the value using the given formatter.

impl Default for VnodeCount

fn default() -> VnodeCount

Returns the “default value” for a type.

impl Hash for VnodeCount

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

Feeds this value into the given Hasher.

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

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for VnodeCount

fn eq(&self, other: &VnodeCount) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for VnodeCount

impl Eq for VnodeCount

impl StructuralPartialEq for VnodeCount