//! - `MultiAsset`: A description of a single asset, either an instance of a non-fungible or some
//! - `Wild`: A single asset wildcard, this can either be "all" assets, or all assets of a specific
/// Use the value of `self` along with a `fun` fungibility specifier to create the corresponding
/// Use the value of `self` along with a `fun` fungibility specifier to create the corresponding
/// Either an amount of a single fungible asset, or a single well-identified non-fungible asset.
/// There are a number of invariants which the construction and mutation functions must ensure are
/// All assets in Holding, up to `u32` individual assets (different instances of non-fungibles