August 2019
Intermediate to advanced
486 pages
13h 52m
English
Content preview from Mastering Blockchain Programming with Solidity
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Address list pattern
The address list pattern is used to maintain a curated list of addresses by the owner.
In contracts, there are some situations in which you would need a curated list of addresses. For example, you would need a list of whitelisted addresses that are allowed to call a certain function of your contract. Another example is when you want to maintain a list of supported tokens addresses to allow your contracts to interact with these selected tokens only.
In the address list pattern, adding and removing addresses from the list can only be done by the owner of the contract. In the following code, we have an AddressList contract:
contract AddressList is Ownable { mapping(address => bool) internal map; function add(address _address) ...