pragma solidity ^0.4.18; contract Membership { bool public win; mapping (address => bool) public members; function becomeMember() payable { require(msg.value == 1 ether); members[msg.sender] = true; } modifier onlyMember() { require(members[msg.sender] == true); _; } function winGame() onlyMember { win = true; // do whatever you want } }
0.4.19