These are chat archives for ethereum/tutorials

Nov 2016
Pawan Singhal
Nov 08 2016 04:48
Hi there
I am getting this error while deploying the standard code given on Etherium website to generate tokens on test net
Error: e.message.replace is not a function...
Please can someone help me on this?

this is the code: pragma solidity ^0.4.2;
contract tokenRecipient { function receiveApproval(address _from, uint256 _value, address _token, bytes _extraData); }

contract MyToken {
/ Public variables of the token /
string public standard = 'Token 0.1';
string public name;
string public symbol;
uint8 public decimals;
uint256 public totalSupply;

/* This creates an array with all balances */
mapping (address => uint256) public balanceOf;
mapping (address => mapping (address => uint256)) public allowance;

/* This generates a public event on the blockchain that will notify clients */
event Transfer(address indexed from, address indexed to, uint256 value);

/* Initializes contract with initial supply tokens to the creator of the contract */
function MyToken(
    uint256 initialSupply,
    string tokenName,
    uint8 decimalUnits,
    string tokenSymbol
    ) {
    balanceOf[msg.sender] = initialSupply;              // Give the creator all initial tokens
    totalSupply = initialSupply;                        // Update total supply
    name = tokenName;                                   // Set the name for display purposes
    symbol = tokenSymbol;                               // Set the symbol for display purposes
    decimals = decimalUnits;                            // Amount of decimals for display purposes

/* Send coins */
function transfer(address _to, uint256 _value) {
    if (balanceOf[msg.sender] < _value) throw;           // Check if the sender has enough
    if (balanceOf[_to] + _value < balanceOf[_to]) throw; // Check for overflows
    balanceOf[msg.sender] -= _value;                     // Subtract from the sender
    balanceOf[_to] += _value;                            // Add the same to the recipient
    Transfer(msg.sender, _to, _value);                   // Notify anyone listening that this transfer took place

/* Allow another contract to spend some tokens in your behalf */
function approve(address _spender, uint256 _value)
    returns (bool success) {
    allowance[msg.sender][_spender] = _value;
    return true;

/* Approve and then comunicate the approved contract in a single tx */
function approveAndCall(address _spender, uint256 _value, bytes _extraData)
    returns (bool success) {
    tokenRecipient spender = tokenRecipient(_spender);
    if (approve(_spender, _value)) {
        spender.receiveApproval(msg.sender, _value, this, _extraData);
        return true;

/* A contract attempts to get the coins */
function transferFrom(address _from, address _to, uint256 _value) returns (bool success) {
    if (balanceOf[_from] < _value) throw;                 // Check if the sender has enough
    if (balanceOf[_to] + _value < balanceOf[_to]) throw;  // Check for overflows
    if (_value > allowance[_from][msg.sender]) throw;   // Check allowance
    balanceOf[_from] -= _value;                          // Subtract from the sender
    balanceOf[_to] += _value;                            // Add the same to the recipient
    allowance[_from][msg.sender] -= _value;
    Transfer(_from, _to, _value);
    return true;

/* This unnamed function is called whenever someone tries to send ether to it */
function () {
    throw;     // Prevents accidental sending of ether


Pawan Singhal
Nov 08 2016 06:07
How can I retrieve the password of my Ethereum wallet, I have forgotten it?
Vlad Suciu
Nov 08 2016 16:39
Are there any tutorials about state channels? Can there be state channels with more than 2 participants? how are they implemented?
Nov 08 2016 17:45
Hi all! is it possible to set rules
regarding coin/token issuance: is it possible to set rules based on external data? through API for example
2) when issuing new coins/token is it possible to distribute proportionally to actual token's owner?
Nov 08 2016 17:51