ERC20

A Re-entry protected and overloadedable implimentation of the ERC20 token standard.

0.4.4-o0ragman0o

updated:26-July-2017

author: Darryl Morris

license: MIT

ABI

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Overview

This contract impliments the ERC20 API functions of totalSupply() balanceOf() allowed() transfer() transferFrom() and allowance().

Re-entry protection on the state mutating functions prevents a malicious contract from reentering the contract in an attempt to change state while in a different memory context.

The totalSupply() balanceOf() and allowance() getters are explicitly defined to allow for function overloading in deriving contracts where such contracts may return calculated values. The respective internal state variables are totSupply balance and allowed

This implimentation uses a single internal transfer function xfer(from, to, amount) called by the overloadable public functions transfer() and transferFrom. This allows deriving contracts to overload the public functions with additional parameter validation and dynamic behaviour without having to rewrite the core transfer logic.

Functions

totalSupply

function totalSupply() public constant returns (uint);

Returns the total supply of tokens

symbol

function symbol() public constant returns (string);

Returns the trading symbol of the token

balanceOf

function balanceOf(address _addr) public constant returns (uint);

Returns the balance of tokens of a holder _addr The address of a token holder

allowance

function allowance(address _owner, address _spender) public constant returns (uint);

Returns the amount of tokens the _spender is allowed to transfer _owner The address of a token holder _spender the address of a third-party

transfer

function transfer(address _to, uint256 _amount) public returns (bool);

Sends the _amount of tokens from msg.sender to _to. Returns success. _to The address of the recipient _amount The amount of tokens to transfer

transferFrom

function transferFrom(address _from, address _to, uint256 _amount)
        public returns (bool);

Sends the _amount of tokens from _from to _to on the condition the amount has been approved by _from. _from The address of the sender. _to The address of the recipient. _amount The amount of tokens to transfer.

approve

function approve(address _spender, uint256 _amount) public returns (bool);

Approves and amount of tokens that can be sent by a thrid-party _spender The address of the approved spender _amount The amount of tokens to transfer

Events

Transfer

event Transfer(address indexed _from, address indexed _to, uint256 _value);`

Triggered when tokens are transferred.

Approval

event Approval(address indexed _owner, address indexed _spender, uint256 _value);

Triggered whenever approve(address _spender, uint256 _value) is called.