FDF智能合约互助公排系统开发源码技术讲解
智能合约包含了有关交易的所有信息，只有在满足要求后才会执行结果操作。智能合约和传统纸质合约的区别在于智能合约是由计算机生成的。因此，代码本身解释了参与方的相关义务。
事实上，智能合约系统的参与方通常是互联网上的陌生人，受制于有约束力的数字化协议。本质上，智能合约是一个数字合约，除非满足要求，否则不会产生结果。
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) }
}
}}
