FDF智能合約互助公排系統(tǒng)開發(fā)源碼技術(shù)講解
智能合約包含了有關(guān)交易的所有信息，只有在滿足要求后才會執(zhí)行結(jié)果操作。智能合約和傳統(tǒng)紙質(zhì)合約的區(qū)別在于智能合約是由計算機生成的。因此，代碼本身解釋了參與方的相關(guān)義務(wù)。
事實上，智能合約系統(tǒng)的參與方通常是互聯(lián)網(wǎng)上的陌生人，受制于有約束力的數(shù)字化協(xié)議。本質(zhì)上，智能合約是一個數(shù)字合約，除非滿足要求，否則不會產(chǎn)生結(jié)果。
Proxy.sol
pragma solidity ^0.4.24;/**
* @title Proxy
* @dev Gives the possibility to delegate any call to a foreign implementation.
*/contract Proxy {
?/**
?* @dev Tells the address of the implementation where every call will be delegated.
?* @return address of the implementation to which it will be delegated
?*/
?function implementation() public view returns (address);
?/**
?* @dev Fallback function allowing to perform a delegatecall to the given implementation.
?* This function will return whatever the implementation call returns
?*/
?function () payable public {
? ?address _impl = implementation();
? ?require(_impl != address(0));
? ?assembly {
? ? ?let ptr := mload(0x40)
? ? ?calldatacopy(ptr, 0, calldatasize)
? ? ?let result := delegatecall(gas, _impl, ptr, calldatasize, 0, 0)
? ? ?let size := returndatasize ? ? ?returndatacopy(ptr, 0, size)
? ? ?switch result ? ? ?case 0 { revert(ptr, size) }
? ? ?default { return(ptr, size) }
? ?}
?}}
