Trait frame_support::traits::tokens::nonfungible::Inspect

pub trait Inspect<AccountId> {
    type InstanceId;
    fn owner(instance: &Self::InstanceId) -> Option<AccountId>;

    fn attribute(_instance: &Self::InstanceId, _key: &[u8]) -> Option<Vec<u8>> { ... }
    fn typed_attribute<K: Encode, V: Decode>(
        instance: &Self::InstanceId, 
        key: &K
    ) -> Option<V> { ... }
    fn can_transfer(_instance: &Self::InstanceId) -> bool { ... }
}

Trait for providing an interface to a read-only NFT-like set of asset instances.

Associated Types

type InstanceId

Type for identifying an asset instance.

Required methods

fn owner(instance: &Self::InstanceId) -> Option<AccountId>

Returns the owner of asset instance, or None if the asset doesn’t exist or has no owner.

Provided methods

fn attribute(_instance: &Self::InstanceId, _key: &[u8]) -> Option<Vec<u8>>

Returns the attribute value of instance corresponding to key.

By default this is None; no attributes are defined.

fn typed_attribute<K: Encode, V: Decode>(
    instance: &Self::InstanceId,
    key: &K
) -> Option<V>

Returns the strongly-typed attribute value of instance corresponding to key.

By default this just attempts to use attribute.

fn can_transfer(_instance: &Self::InstanceId) -> bool

Returns true if the asset instance may be transferred.

Default implementation is that all assets are transferable.

Implementors

impl<F: Inspect<AccountId>, A: Get<<F as Inspect<AccountId>>::ClassId>, AccountId> Inspect<AccountId> for ItemOf<F, A, AccountId>

type InstanceId = <F as Inspect<AccountId>>::InstanceId