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Contracts · medium

4. Starknet Contract Storage (#[storage])

Reading and writing persistent contract state.

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State is defined in a `Storage` struct. Storage variables use `read()` and `write()`. Mappings are modeled using `Map<Key, Value>` (or legacy `LegacyMap`).

cairo
#[storage]
struct Storage {
    names: Map<ContractAddress, felt252>,
}

fn set_name(ref self: ContractState, name: felt252) {
    let caller = get_caller_address();
    self.names.write(caller, name);
}

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Check your understanding

  1. 1. How do you write a value to a storage variable in Cairo contracts?

  2. 2. What type represents account addresses in Starknet Cairo?

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