A dictionary is created using the default_dict_new() module from the Common Library. Every key will return the default value unless it is explicitly set.


  1. Get a pointer to a new dictionary with default_dict_new().
  2. Assert its integrity with default_dict_finalize().
  3. Assign a value to a key dict_write().
  4. Read the value of a key dict_read().
%lang starknet
%builtins range_check

from starkware.cairo.common.default_dict import (
    default_dict_new, default_dict_finalize)
from starkware.cairo.common.dict import (
    dict_write, dict_read, dict_update)

# Returns the value for the specified key in a dictionary.
func get_value_of_keys{range_check_ptr}(
        key_1 : felt, key_2 : felt, key_3 : felt) -> (
        val_1 : felt, val_2 : felt, val_3 : felt):
    # First create an empty dictionary and finalize it.
    # All keys will initially have value 13. {key: 13}.
    let initial_value = 13
    let (local dict) = default_dict_new(default_value=initial_value)
    # Finalize the dictionary. This ensures default value is correct.

    # Then add {key: val} pairs.
    dict_write{dict_ptr=dict}(key=4, new_value=17)  # {4: 17}.
    dict_write{dict_ptr=dict}(key=10, new_value=6)  # {10: 6}.

    # Check {key: value} pair is correct.
    let (key_4_val) = dict_read{dict_ptr=dict}(key=4)
    assert key_4_val = 17

    # Update a key.
        prev_value=17, new_value=18)  # {4: 17} -> {4: 18}

    # Check that an unused key returns the default value.
    let (unused_key_999_val) = dict_read{dict_ptr=dict}(
    assert unused_key_999_val = 13

    # Get value of the requested keys.
    let (val_1) = dict_read{dict_ptr=dict}(key_1)
    let (val_2) = dict_read{dict_ptr=dict}(key_2)
    let (val_3) = dict_read{dict_ptr=dict}(key_3)
    return (val_1, val_2, val_3)

Save as default_dict.cairo.


Then, to compile:

starknet-compile default_dict.cairo \
    --output default_dict_compiled.json \
    --abi default_dict_contract_abi.json


Then, to deploy:

starknet deploy --contract default_dict_compiled.json \

Deploy transaction was sent.
Contract address: 0x0239d703aabc8f9202a3c9c7b2f6969bdb0af23981fcb21624135c3c32d006d4
Transaction ID: 198291

Note: Remove the zero after the x, 0x[0]12345. E.g., 0x0123abc becomes 0x123abc.


Check the status of the transaction:

starknet tx_status --network=alpha --id=198291

    "block_id": 44334,
    "tx_status": "PENDING"

The block and the contract


Then, to interact:

starknet call \
    --network=alpha \
    --address 0x239d703aabc8f9202a3c9c7b2f6969bdb0af23981fcb21624135c3c32d006d4 \
    --abi default_dict_contract_abi.json \
    --function get_value_of_keys \
    --inputs 2 4 10

13 18 6

Key-value pairs returned are:

  • {2: 13} A default value.
  • {4: 18} the key that was assigned and then updated.
  • {10: 6} the key that was assigned.

Status options:

  • NOT_RECEIVED: The transaction has not been received yet (i.e., not written to storage).
  • RECEIVED: The transaction was received by the operator.
    • PENDING: The transaction passed the validation and is waiting to be sent on-chain.
      • REJECTED: The transaction failed validation and thus was skipped.
      • ACCEPTED_ONCHAIN: The transaction was accepted on-chain.

Visit the voyager explorer to see the transactions.