Struct multiversx_sc::storage::mappers::UniqueIdMapper

pub struct UniqueIdMapper<SA, A = CurrentStorage>
where
    SA: StorageMapperApi,
    A: StorageAddress<SA>,
{ /* private fields */ }

Holds the values from 1 to N with as little storage interaction as possible If Mapper[i] = i, then it stores nothing, i.e. “0” If Mapper[i] is equal to another value, then it stores the value

Implementations

impl<SA> UniqueIdMapper<SA, ManagedAddress<SA>>

where SA: StorageMapperApi,

pub fn new_from_address( address: ManagedAddress<SA>, base_key: StorageKey<SA> ) -> Self

impl<SA, A> UniqueIdMapper<SA, A>

where SA: StorageMapperApi, A: StorageAddress<SA>,

pub fn len(&self) -> usize

pub fn is_empty(&self) -> bool

pub fn get(&self, index: usize) -> UniqueId

Gets the value for the given index. If the entry is empty, index is returned.

pub fn iter(&self) -> Iter<'_, SA, A>

Provides a forward iterator.

impl<SA> UniqueIdMapper<SA, CurrentStorage>

where SA: StorageMapperApi,

pub fn set_initial_len(&mut self, len: usize)

Initializes the mapper’s length. This may not be set again afterwards.

pub fn swap_remove(&mut self, index: usize) -> UniqueId

Gets the value from the index and removes it. The value is replaced by the last item, and length is decremented.

pub fn set(&mut self, index: usize, id: UniqueId)

Sets the value at the given index. If index == id, then the entry is cleared.

Trait Implementations

impl<'a, SA, A> IntoIterator for &'a UniqueIdMapper<SA, A>

where SA: StorageMapperApi, A: StorageAddress<SA>,

type Item = usize

The type of the elements being iterated over.

type IntoIter = Iter<'a, SA, A>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl<SA> StorageMapper<SA> for UniqueIdMapper<SA, CurrentStorage>

where SA: StorageMapperApi,

fn new(base_key: StorageKey<SA>) -> Self

Will be called automatically by the #[storage_mapper] annotation generated code.

impl<SA> TopEncodeMulti for UniqueIdMapper<SA, CurrentStorage>

where SA: StorageMapperApi,

Behaves like a MultiResultVec when an endpoint result.

fn multi_encode_or_handle_err<O, H>( &self, output: &mut O, h: H ) -> Result<(), H::HandledErr>

where O: TopEncodeMultiOutput, H: EncodeErrorHandler,

Version of top_encode that can handle errors as soon as they occur. For instance in can exit immediately and make sure that if it returns, it is a success. By not deferring error handling, this can lead to somewhat smaller bytecode.

fn multi_encode<O>(&self, output: &mut O) -> Result<(), EncodeError>

where O: TopEncodeMultiOutput,

Attempt to serialize the value to ouput.

impl<SA> TypeAbi for UniqueIdMapper<SA, CurrentStorage>

where SA: StorageMapperApi,

Behaves like a MultiResultVec when an endpoint result.

fn type_name() -> TypeName

fn provide_type_descriptions<TDC: TypeDescriptionContainer>( accumulator: &mut TDC )

A type can provide more than its own name. For instance, a struct can also provide the descriptions of the type of its fields. TypeAbi doesn’t care for the exact accumulator type, which is abstracted by the TypeDescriptionContainer trait.

impl<SA> CodecFrom<UniqueIdMapper<SA>> for MultiValueEncoded<SA, usize>

where SA: StorageMapperApi,