add missing import + remove nested mappings

corelib/src/starknet/storage/map.cairo

@@ -61,28 +61,31 @@
 //! Basic usage with a single mapping:
 //!
 //! ```
+//! use core::starknet::ContractAddress;
+//! use core::starknet::storage::{Map, StorageMapReadAccess, StoragePathEntry,
+//! StoragePointerReadAccess};
+//!
 //! #[storage]
 //! struct Storage {
 //!     balances: Map<ContractAddress, u256>,
 //! }
 //!
-//! fn read_storage(self: @ContractState) {
+//! fn read_storage(self: @ContractState, address: ContractAddress) {
 //!     let balance = self.balances.read(address);
 //!     let balance = self.balances.entry(address).read();
 //! }
 //! ```
 //!
-//! Nested mappings:
+//! For nested mappings, only path-based access is available:
 //!
 //! ```
 //! #[storage]
 //! struct Storage {
 //!     allowances: Map<ContractAddress, Map<ContractAddress, u256>>,
 //! }
 //!
-//! fn read_storage(self: @ContractState) {
+//! fn read_storage(self: @ContractState, owner: ContractAddress, spender: ContractAddress) {
 //!     let allowance = self.allowances.entry(owner).entry(spender).read();
-//!     let allowance = self.allowances.read(owner, spender);
 //! }
 //! ```
 
@@ -97,18 +100,17 @@ use super::{
 /// # Examples
 ///
 /// ```
+/// use core::starknet::ContractAddress;
+/// use core::starknet::storage::{Map, StorageMapReadAccess};
+///
 /// #[storage]
 /// struct Storage {
 ///     balances: Map<ContractAddress, u256>,
-///     allowances: Map<ContractAddress, Map<ContractAddress, u256>>,
 /// }
 ///
-/// fn read_storage(self: @ContractState) {
+/// fn read_storage(self: @ContractState, address: ContractAddress) {
 ///     // Read from single mapping
 ///     let balance = self.balances.read(address);
-///
-///     // Read from nested mapping
-///     let allowance = self.allowances.read(owner, spender);
 /// }
 /// ```
 pub trait StorageMapReadAccess<TMemberState> {
@@ -124,18 +126,17 @@ pub trait StorageMapReadAccess<TMemberState> {
 /// # Examples
 ///
 /// ```
+/// use core::starknet::ContractAddress;
+/// use core::starknet::storage::{Map, StorageMapWriteAccess};
+///
 /// #[storage]
 /// struct Storage {
 ///     balances: Map<ContractAddress, u256>,
-///     allowances: Map<ContractAddress, Map<ContractAddress, u256>>,
 /// }
 ///
-/// fn write_storage(ref self: ContractState) {
+/// fn write_storage(ref self: ContractState, address: ContractAddress) {
 ///     // Write to single mapping
 ///     self.balances.write(address, 100);
-///
-///     // Write to nested mapping
-///     self.allowances.write(owner, spender, 50);
 /// }
 /// ```
 pub trait StorageMapWriteAccess<TMemberState> {
@@ -153,6 +154,9 @@ pub trait StorageMapWriteAccess<TMemberState> {
 /// # Examples
 ///
 /// ```
+/// use core::starknet::ContractAddress;
+/// use core::starknet::storage::{Map, StoragePathEntry};
+///
 /// #[storage]
 /// struct Storage {
 ///     balances: Map<ContractAddress, u256>,