Как типы кортежей кодируются в сигнатуре функции для создания 4-байтового селектора функций? Официальная спецификация ничего не говорит о типах кортежей.
Используйте (type1,type2,...)
для представления структур.
Например, fillOrder
функция в 0x 2.0 :
function fillOrder(
Order memory order,
uint256 takerAssetFillAmount,
bytes memory signature
)
public
returns (LibFillResults.FillResults memory fillResults);
struct Order {
address makerAddress; // Address that created the order.
address takerAddress; // Address that is allowed to fill the order. If set to 0, any address is allowed to fill the order.
address feeRecipientAddress; // Address that will recieve fees when order is filled.
address senderAddress; // Address that is allowed to call Exchange contract methods that affect this order. If set to 0, any address is allowed to call these methods.
uint256 makerAssetAmount; // Amount of makerAsset being offered by maker. Must be greater than 0.
uint256 takerAssetAmount; // Amount of takerAsset being bid on by maker. Must be greater than 0.
uint256 makerFee; // Amount of ZRX paid to feeRecipient by maker when order is filled. If set to 0, no transfer of ZRX from maker to feeRecipient will be attempted.
uint256 takerFee; // Amount of ZRX paid to feeRecipient by taker when order is filled. If set to 0, no transfer of ZRX from taker to feeRecipient will be attempted.
uint256 expirationTimeSeconds; // Timestamp in seconds at which order expires.
uint256 salt; // Arbitrary number to facilitate uniqueness of the order's hash.
bytes makerAssetData; // Encoded data that can be decoded by a specified proxy contract when transferring makerAsset. The last byte references the id of this proxy.
bytes takerAssetData; // Encoded data that can be decoded by a specified proxy contract when transferring takerAsset. The last byte references the id of this proxy.
}
Селектор функций рассчитывается с использованием:
fillOrder((address,address,address,address,uint256,uint256,uint256,uint256,uint256,uint256,bytes,bytes),uint256,bytes)
Это создает keccak256 из: b4be83d519a652e54a6073d7e55643f575508112b09dcc74264b807477b576c5
, а первые 4 байта:b4be83d5
Вы можете подтвердить это, посмотрев на этот tx, который называется fillOrder :