# nat64

The `CandidType` object `nat64` corresponds to the Candid type nat64, is inferred to be a TypeScript `bigint`, and will be decoded into a JavaScript BigInt at runtime.

TypeScript or JavaScript:

    import { Canister, nat64, query } from 'azle';

    export default Canister({
        getNat64: query([], nat64, () => {
            return 18_446_744_073_709_551_615n;
        }),
        printNat64: query([nat64], nat64, (nat64) => {
            console.log(typeof nat64);
            return nat64;
        })
    });

Candid:

    service : () -> {
        getNat64 : () -> (nat64) query;
        printNat64 : (nat64) -> (nat64) query;
    }

dfx:

    dfx canister call candid_canister printNat64 '(18_446_744_073_709_551_615 : nat64)'
    (18_446_744_073_709_551_615 : nat64)