Trait totem_common::StorageMapExt

source · [−]

pub trait StorageMapExt<K, V> where
    Self: StorageMap<K, V>,
    K: FullEncode + Encode + EncodeLike,
    V: FullCodec + Decode + FullEncode + Encode + EncodeLike, {
    fn mutate_or_err<KeyArg: EncodeLike<K>, F: FnOnce(&mut V)>(
        key: KeyArg, 
        f: F
    ) -> DispatchResultWithPostInfo { ... }
}

Expand description

Adds behavior to StorageMaps.

Provided methods

fn mutate_or_err<KeyArg: EncodeLike<K>, F: FnOnce(&mut V)>(
key: KeyArg,
f: F
) -> DispatchResultWithPostInfo

If the key exists in the map, modifies it with the provided function, otherwise, an error is returned.

Implementors

impl<T, K, V> StorageMapExt<K, V> for T where
    T: StorageMap<K, V>,
    K: FullEncode + Encode + EncodeLike,
    V: FullCodec + Decode + FullEncode + Encode + EncodeLike,