macro_rules! wrap_storage_double_map {
(storage: $storage: ident, name: $name: ident, key1: $key1: ty,
key2: $key2: ty, value: $val: ty) => { ... };
}Expand description
Creates new type with specified name and key1-key2-value types and
implements DoubleMapStorage for it based on specified storage,
which is a Substrate’s StorageDoubleMap.
This macro main purpose is to follow newtype pattern
and avoid Substrate dependencies in gear_common.
Requires PhantomData be in scope: from std, core or sp_std.
Requires Config be in scope of the crate root where it called.