Struct EnumTable

pub struct EnumTable<K: Enumable, V, const N: usize> { /* private fields */ }

A table that associates each variant of an enumeration with a value.

EnumTable is a generic struct that uses an enumeration as keys and stores associated values. It provides constant-time access to the values based on the enumeration variant.

Implementations

impl<K: Enumable, V, const N: usize> EnumTable<K, V, N>

pub const fn new(table: [(Discriminant<K>, V); N]) -> Self

Creates a new EnumTable with the given table of discriminants and values.

Arguments

• table - An array of tuples where each tuple contains a discriminant of an enumeration variant and its associated value.

pub fn new_with_fn(f: impl FnMut(&K) -> V) -> Self

Create a new EnumTable with a function that takes a variant and returns a value. If you want to define it in const, use crate::et macro Creates a new EnumTable using a function to generate values for each variant.

Arguments

• f - A function that takes a reference to an enumeration variant and returns a value to be associated with that variant.

pub const fn get(&self, variant: &K) -> &V

Returns a reference to the value associated with the given enumeration variant.

Arguments

• variant - A reference to an enumeration variant.

pub const fn get_mut(&mut self, variant: &K) -> &mut V

Returns a mutable reference to the value associated with the given enumeration variant.

Arguments

• variant - A reference to an enumeration variant.

pub const fn const_set(&mut self, variant: &K, value: V)

const function is not callable drop. So, we use forget to avoid calling drop. Careful, not to call drop on the old value. Sets the value associated with the given enumeration variant in a constant context.

Arguments

• variant - A reference to an enumeration variant.
• value - The new value to associate with the variant.

Safety

This method uses std::mem::forget to avoid calling drop on the old value. Be careful not to call drop on the old value manually.

pub fn set(&mut self, variant: &K, value: V)

Sets the value associated with the given enumeration variant.

Arguments

• variant - A reference to an enumeration variant.
• value - The new value to associate with the variant.

pub const fn len(&self) -> usize

Returns the number of generic N

pub const fn is_empty(&self) -> bool

Returns false since the table is never empty.

Trait Implementations

impl<K: Clone + Enumable, V: Clone, const N: usize> Clone for EnumTable<K, V, N>

fn clone(&self) -> EnumTable<K, V, N>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<K: Debug + Enumable, V: Debug, const N: usize> Debug for EnumTable<K, V, N>

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

Formats the value using the given formatter.

impl<K: Enumable, V: Default, const N: usize> Default for EnumTable<K, V, N>

fn default() -> Self

Returns the “default value” for a type.

impl<K: Enumable, V, const N: usize> Index<K> for EnumTable<K, V, N>

type Output = V

The returned type after indexing.

fn index(&self, index: K) -> &Self::Output

Performs the indexing (container[index]) operation.

impl<K: Enumable, V, const N: usize> IndexMut<K> for EnumTable<K, V, N>

fn index_mut(&mut self, index: K) -> &mut Self::Output

Performs the mutable indexing (container[index]) operation.

impl<K: Copy + Enumable, V: Copy, const N: usize> Copy for EnumTable<K, V, N>