How can I instantiate an array of addresses?

Question

I simply want to create an array with stuff in it. Everything I try is an error message in mist. Even this code snippet I got straight from the docs wont compile:

contract C {
    uint someVariable;
    uint[] data;
    function f() {
        uint[] x = data;
        x.push(2);
    }
}

I simply want to do something that would be analogous to this ruby:

arr = ['0x36eaf79c12e96a3dc6f53426c', '0xf235aa56dd96bda02acfb361e']

I dont need the size to be dynamic, and the type is address.

Answer 1

You're doing something wrong. This works perfectly fine. Try it in the browser compiler.

contract Test {
    address[] public arr =  [0x36eaf79c12e96a3dc6f53426c, 0xf235aa56dd96bda02acfb361e];
}

Answer 2

Here's an example I created using testrpc for this question:

After setting up testrpc and attaching geth:

testrpc -a 10
geth attach rpc:http://localhost:8545

Deploy the following contract on the geth command line:

pragma solidity ^0.4.6;
contract AddressList {  
    event addressregistered(address addy);

    uint public NoMembers; 
    address[] public MemberAddresses;

    function registerAddress() { 
        MemberAddresses.push(msg.sender);    
        NoMembers = MemberAddresses.length;    
        addressregistered(msg.sender);
        }  
}

var addresslistContract = web3.eth.contract([{"constant":false,"inputs":[],"name":"registerAddress","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"NoMembers","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"","type":"uint256"}],"name":"MemberAddresses","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"anonymous":false,"inputs":[{"indexed":false,"name":"addy","type":"address"}],"name":"addressregistered","type":"event"}]);
var addresslist = addresslistContract.new(
   {
     from: web3.eth.accounts[0], 
     data: '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', 
     gas: '4700000'
   }, function (e, contract){
    console.log(e, contract);
    if (typeof contract.address !== 'undefined') {
         console.log('Contract mined! address: ' + contract.address + ' transactionHash: ' + contract.transactionHash);
    }
 })

Then store, for example, 10 addresses in the contract:

for (var x = 0; x < 10; x++){
    addresslist.registerAddress({from:eth.accounts[x],gas:3000000}) 
}

Answer 3

address[3] memory users;
users[0] = 0x...;
users[1] = 0x...;
users[2] = 0x...;