Trait AssetIdAllocator 

pub trait AssetIdAllocator<AssetId> {
    // Required methods
    fn next() -> Option<AssetId>;
    fn advance() -> Result<(), ()>;
    fn advance_from(id: &AssetId) -> Result<(), ()>;
}

Allocates the asset ids used by create.

Configure Config::AssetIdAllocator with () to leave create unconstrained, or with an impl such as AutoIncAssetId to enforce an allocation policy.

Required Methods

fn next() -> Option<AssetId>

The only id create may use, or None to accept any id not currently in use.

fn advance() -> Result<(), ()>

Allocate the id returned by Self::next, after a successful create.

Returns Err if the id space is exhausted.

fn advance_from(id: &AssetId) -> Result<(), ()>

Allocate id, after a successful force_create, so Self::next can never return it.

Returns Err if the id space is exhausted.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl<AssetId> AssetIdAllocator<AssetId> for ()

No allocation policy: create accepts any unused id and NextAssetId has no effect.

fn next() -> Option<AssetId>

fn advance() -> Result<(), ()>

fn advance_from(_: &AssetId) -> Result<(), ()>

Implementors

impl<T: Config<I>, I: 'static> AssetIdAllocator<<T as Config<I>>::AssetId> for AutoIncAssetId<T, I>

where T::AssetId: Incrementable + PartialOrd,