Avalanche is a network composed of multiple blockchains. Each blockchain is an instance of a Virtual Machine (VM), much like an object in an object-oriented language is an instance of a class. That is, the VM defines the behavior of the blockchain.
Subnet EVM is the Virtual Machine (VM) that defines the Subnet Contract Chains. Subnet EVM is a simplified version of Coreth VM (C-Chain).
This chain implements the Ethereum Virtual Machine and supports Solidity smart contracts as well as most other Ethereum client functionality.
The Subnet EVM runs in a separate process from the main AvalancheGo process and communicates with it over a local gRPC connection.
[v0.1.0] AvalancheGo@v1.7.0-v1.7.4
[v0.1.1-v0.1.2] AvalancheGo@v1.7.5-v1.7.6
[v0.2.0] AvalancheGo@v1.7.7-v1.7.9
[v0.2.1] AvalancheGo@v1.7.10
The Subnet EVM supports the following API namespaces:
ethpersonaltxpooldebug
Only the eth namespace is enabled by default.
Full documentation for the C-Chain's API can be found here.
The Subnet EVM is compatible with almost all Ethereum tooling, including Remix, Metamask and Truffle.
- Added configurable fees and gas limits in genesis
- Merged Avalanche hardforks into the single "Subnet EVM" hardfork
- Removed Atomic Txs and Shared Memory
- Removed Multicoin Contract and State
See Create a Local EVM Subnet.
When creating an instance of the subnet-evm, you will need to define the genesis state of the new chain. Part of this includes defining the genesis allocation (setting the starting balances for whatever addresses you want). If you don't provide any genesis allocation, you won't be able to interact with your new chain (all transactions require a fee to be paid from the sender's balance).
To specify a genesis allocation, populate the alloc field in the genesis JSON as follows:
"alloc": {
"8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC": {
"balance": "0x52B7D2DCC80CD2E4000000"
},
"Ab5801a7D398351b8bE11C439e05C5B3259aeC9B": {
"balance": "0xa796504b1cb5a7c0000"
}
},The keys in the allocation are hex addresses without the canonical 0x prefix.
The balances are denominated in Wei (10^18 Wei = 1 Whole Unit of Native Token) and expressed as
hex strings with the canonical 0x prefix. You can use this converter
to translate between decimal and hex numbers.
The above example yields the following genesis allocations (denominated in whole units of the native token ie. 1 AVAX/1 WAGMI):
0x8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC: 100000000 (0x52B7D2DCC80CD2E4000000=100000000000000000000000000 Wei)
0xAb5801a7D398351b8bE11C439e05C5B3259aeC9B: 49463 (0xa796504b1cb5a7c0000=49463000000000000000000 Wei)
A fully populated genesis JSON with the above allocation would look like (note the alloc field):
{
"config": {
"chainId": 99999,
"homesteadBlock": 0,
"eip150Block": 0,
"eip150Hash": "0x2086799aeebeae135c246c65021c82b4e15a2c451340993aacfd2751886514f0",
"eip155Block": 0,
"eip158Block": 0,
"byzantiumBlock": 0,
"constantinopleBlock": 0,
"petersburgBlock": 0,
"istanbulBlock": 0,
"muirGlacierBlock": 0,
"subnetEVMTimestamp": 0,
"feeConfig": {
"gasLimit": 20000000,
"minBaseFee": 1000000000,
"targetGas": 100000000,
"baseFeeChangeDenominator": 48,
"minBlockGasCost": 0,
"maxBlockGasCost": 10000000,
"targetBlockRate": 2,
"blockGasCostStep": 500000
}
},
"alloc": {
"8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC": {
"balance": "0x52B7D2DCC80CD2E4000000"
},
"Ab5801a7D398351b8bE11C439e05C5B3259aeC9B": {
"balance": "0xa796504b1cb5a7c0000"
}
},
"nonce": "0x0",
"timestamp": "0x0",
"extraData": "0x00",
"gasLimit": "0x1312D00",
"difficulty": "0x0",
"mixHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
"coinbase": "0x0000000000000000000000000000000000000000",
"number": "0x0",
"gasUsed": "0x0",
"parentHash": "0x0000000000000000000000000000000000000000000000000000000000000000"
}By default, all fees are burned (sent to the blackhole address). However, it is possible to enable block producers to set a fee recipient (get compensated for blocks they produce).
To enable this feature, you'll need to add the following to your
genesis file (under the "config" key):
{
"config": {
"allowFeeRecipients": true
}
}Next, you'll need to update your chain config with the following:
{
"feeRecipient": "<YOUR 0x-ADDRESS>"
}Note: If you enable this feature but a validator doesn't specify a "feeRecipient", the fees will be burned in blocks they produce.
A transaction is "regossiped" when the node does not find the transaction in
a block after priority-regossip-frequency (defaults to 1m). By default, up to 16 transactions
(max 1 per address) are regossiped to validators per minute.
Operators can use "priority regossip" to more aggressively "regossip" transactions for a set of important addresses (like bridge relayers). To do so, you'll need to update your chain config with the following:
{
"priority-regossip-addresses": ["<YOUR 0x-ADDRESS>"]
}By default, up to 32 transactions from priority addresses (max 16 per address) are regossipped to validators per second. You can override these defaults with the following config:
{
"priority-regossip-frequency": "1s",
"priority-regossip-max-txs": 32,
"priority-regossip-addresses": ["<YOUR 0x-ADDRESS>"],
"priority-regossip-txs-per-address": 16
}Subnet EVM can provide custom functionalities with precompiled contracts. These precompiled contracts can be activated through ChainConfig (in genesis or as an upgrade).
If you'd like to restrict who has the ability to deploy contracts on your
subnet, you can provide an AllowList configuration in your genesis file:
{
"config": {
"chainId": 99999,
"homesteadBlock": 0,
"eip150Block": 0,
"eip150Hash": "0x2086799aeebeae135c246c65021c82b4e15a2c451340993aacfd2751886514f0",
"eip155Block": 0,
"eip158Block": 0,
"byzantiumBlock": 0,
"constantinopleBlock": 0,
"petersburgBlock": 0,
"istanbulBlock": 0,
"muirGlacierBlock": 0,
"subnetEVMTimestamp": 0,
"feeConfig": {
"gasLimit": 20000000,
"minBaseFee": 1000000000,
"targetGas": 100000000,
"baseFeeChangeDenominator": 48,
"minBlockGasCost": 0,
"maxBlockGasCost": 10000000,
"targetBlockRate": 2,
"blockGasCostStep": 500000
},
"contractDeployerAllowListConfig": {
"blockTimestamp": 0,
"adminAddresses": ["0x8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC"]
}
},
"alloc": {
"8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC": {
"balance": "0x52B7D2DCC80CD2E4000000"
}
},
"nonce": "0x0",
"timestamp": "0x0",
"extraData": "0x00",
"gasLimit": "0x1312D00",
"difficulty": "0x0",
"mixHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
"coinbase": "0x0000000000000000000000000000000000000000",
"number": "0x0",
"gasUsed": "0x0",
"parentHash": "0x0000000000000000000000000000000000000000000000000000000000000000"
}In this example, 0x8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC is named as the
Admin of the ContractDeployerAllowList. This enables them to add other Admins or to add
Deployers. Both Admins and Deployers can deploy contracts. To provide
a great UX with factory contracts, the tx.Origin is checked for being a valid
deployer instead of the caller of CREATE. This means that factory contracts will still be
able to create new contracts as long as the sender of the original transaction is an allow
listed deployer.
The Stateful Precompile powering the ContractDeployerAllowList adheres to the following Solidity interface at 0x0200000000000000000000000000000000000000 (you can load this interface and interact directly in Remix):
// (c) 2022-2023, Ava Labs, Inc. All rights reserved.
// See the file LICENSE for licensing terms.
// SPDX-License-Identifier: MIT
pragma solidity >=0.8.0;
interface AllowListInterface {
// Set [addr] to have the admin role over the allow list
function setAdmin(address addr) external;
// Set [addr] to be enabled on the allow list
function setEnabled(address addr) external;
// Set [addr] to have no role over the allow list
function setNone(address addr) external;
// Read the status of [addr]
function readAllowList(address addr) external view returns (uint256);
}If you attempt to add a Deployer and you are not an Admin, you will see
something like:
If you attempt to deploy a contract but you are not an Admin not
a Deployer, you will see something like:
The allow list has three roles: None, Deployer, and Admin.
If you call readAllowList(addr) then you can read the current role of addr, which will return a uint256 with a value of 0, 1, or 2, corresponding to the roles None, Deployer, and Admin respectively.
WARNING: if you remove all of the admins from the allow list, it will no longer be possible to update the allow list without modifying the subnet-evm to schedule a network upgrade.
Similar to restricting contract deployers, this precompile restricts which addresses may submit transactions on chain. Like the previous section, you can activate the precompile by including an AllowList configuration in your genesis file:
{
"config": {
"chainId": 99999,
"homesteadBlock": 0,
"eip150Block": 0,
"eip150Hash": "0x2086799aeebeae135c246c65021c82b4e15a2c451340993aacfd2751886514f0",
"eip155Block": 0,
"eip158Block": 0,
"byzantiumBlock": 0,
"constantinopleBlock": 0,
"petersburgBlock": 0,
"istanbulBlock": 0,
"muirGlacierBlock": 0,
"subnetEVMTimestamp": 0,
"feeConfig": {
"gasLimit": 20000000,
"minBaseFee": 1000000000,
"targetGas": 100000000,
"baseFeeChangeDenominator": 48,
"minBlockGasCost": 0,
"maxBlockGasCost": 10000000,
"targetBlockRate": 2,
"blockGasCostStep": 500000
},
"txAllowListConfig": {
"blockTimestamp": 0,
"adminAddresses":["0x8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC"]
}
},
"alloc": {
"8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC": {
"balance": "0x52B7D2DCC80CD2E4000000"
}
},
"nonce": "0x0",
"timestamp": "0x0",
"extraData": "0x00",
"gasLimit": "0x1312D00",
"difficulty": "0x0",
"mixHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
"coinbase": "0x0000000000000000000000000000000000000000",
"number": "0x0",
"gasUsed": "0x0",
"parentHash": "0x0000000000000000000000000000000000000000000000000000000000000000"
}In this example, 0x8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC is named as the
Admin of the ContractDeployerAllowList. This enables them to add other Admins or to add
Allowed. Both Admins and Allowed can submit transactions to the chain.
The Stateful Precompile powering the TxAllowList adheres to the following Solidity interface at 0x0200000000000000000000000000000000000002 (you can load this interface and interact directly in Remix):
// (c) 2022-2023, Ava Labs, Inc. All rights reserved.
// See the file LICENSE for licensing terms.
// SPDX-License-Identifier: MIT
pragma solidity >=0.8.0;
interface AllowListInterface {
// Set [addr] to have the admin role over the allow list
function setAdmin(address addr) external;
// Set [addr] to be enabled on the allow list
function setEnabled(address addr) external;
// Set [addr] to have no role over the allow list
function setNone(address addr) external;
// Read the status of [addr]
function readAllowList(address addr) external view returns (uint256);
}If you attempt to add an Allowed and you are not an Admin, you will see
something like:
If you attempt to submit a transaction but you are not an Admin or not
Allowed, you will see something like: cannot issue transaction from non-allow listed address
The allow list has three roles: None, Allowed, and Admin.
If you call readAllowList(addr) then you can read the current role of addr, which will return a uint256 with a value of 0, 1, or 2, corresponding to the roles None, Allowed, and Admin respectively.
WARNING: if you remove all of the admins from the allow list, it will no longer be possible to update the allow list without modifying the subnet-evm to schedule a network upgrade.
You can mint native(gas) coins with a precompiled contract. In order to activate this feature, you can provide nativeMinterConfig in genesis:
{
"config": {
"chainId": 99999,
"homesteadBlock": 0,
"eip150Block": 0,
"eip150Hash": "0x2086799aeebeae135c246c65021c82b4e15a2c451340993aacfd2751886514f0",
"eip155Block": 0,
"eip158Block": 0,
"byzantiumBlock": 0,
"constantinopleBlock": 0,
"petersburgBlock": 0,
"istanbulBlock": 0,
"muirGlacierBlock": 0,
"subnetEVMTimestamp": 0,
"feeConfig": {
"gasLimit": 20000000,
"minBaseFee": 1000000000,
"targetGas": 100000000,
"baseFeeChangeDenominator": 48,
"minBlockGasCost": 0,
"maxBlockGasCost": 10000000,
"targetBlockRate": 2,
"blockGasCostStep": 500000
},
"contractNativeMinterConfig": {
"blockTimestamp": 0,
"adminAddresses": ["0x8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC"]
}
},
"alloc": {
"8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC": {
"balance": "0x52B7D2DCC80CD2E4000000"
}
},
"nonce": "0x0",
"timestamp": "0x0",
"extraData": "0x00",
"gasLimit": "0x1312D00",
"difficulty": "0x0",
"mixHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
"coinbase": "0x0000000000000000000000000000000000000000",
"number": "0x0",
"gasUsed": "0x0",
"parentHash": "0x0000000000000000000000000000000000000000000000000000000000000000"
}adminAddresses denotes admin accounts who can add other Admin or Minter accounts. Minters and Admins are both eligible to mint native coins for other addresses. ContractNativeMinter uses same methods as in ContractDeployerAllowList.
The Stateful Precompile powering the ContractNativeMinter adheres to the following Solidity interface at 0x0200000000000000000000000000000000000001 (you can load this interface and interact directly in Remix):
// (c) 2022-2023, Ava Labs, Inc. All rights reserved.
// See the file LICENSE for licensing terms.
// SPDX-License-Identifier: MIT
pragma solidity >=0.8.0;
interface NativeMinterInterface {
// Set [addr] to have the admin role over the minter list
function setAdmin(address addr) external;
// Set [addr] to be enabled on the minter list
function setEnabled(address addr) external;
// Set [addr] to have no role over the minter list
function setNone(address addr) external;
// Read the status of [addr]
function readAllowList(address addr) external view returns (uint256);
// Mint [amount] number of native coins and send to [addr]
function mintNativeCoin(address addr, uint256 amount) external;
}Note: Both ContractDeployerAllowList and ContractNativeMinter can be used together.
Subnet-EVM contains example contracts for precompiles under /contract-examples. It's a hardhat project with tests, tasks. For more information see contract examples README.
Thanks to the @0xNeonMonsters for the logo!
The WAGMI ("We're All Going to Make It") Subnet Demo is a high throughput
testbed for EVM (Ethereum Virtual Machine) optimizations. It is parameterized
to run at a factor more capacity than Fuji/Mainnet C-Chain and will be used
to experiment with release candidates before they make it into an
official coreth release.
We created a basic WAGMI explorer that surfaces aggregated usage statistics about the subnet. If you'd like to see any other stats added to this site, please send a DM to @_patrickogrady on Twitter.
Everyone that has used the the C-Chain more than twice (~970k addresses) has been airdropped 10 WGM tokens. With the current fee parameterization, this should be enough for hundreds of txs.
This is one of the first cases of using Avalanche Subnets as a proving ground for changes in a production VM (coreth). Many underestimate how useful the isolation of subnets is for performing complex VM testing on a live network (without impacting the stability of the primary network).
To create WAGMI, all we had to do was run the following command:
subnet-cli wizard \
--node-ids=NodeID-9TCq8np31pHjjhGaHtLjs6ptYYPEt3LGb,NodeID-BrYXghQSu6KKGjuzhs3nrkcB46Wc2yYHy,NodeID-89UCR1CsPzzEHuknxhJHKxuFPNCyPz7Bu,NodeID-Hfm8gpD4DpCz4KTzt2osJPfFvu7az3qiD,NodeID-LkdxkfYhg6nSw1EEUxDUSYPXPwmr2cUet \
--vm-genesis-path=networks/11111/genesis.json \
--vm-id=srEXiWaHuhNyGwPUi444Tu47ZEDwxTWrbQiuD7FmgSAQ6X7Dy \
--chain-name=wagmiThis added these NodeIDs as validators on Fuji, created the WAGMI Subnet, added all validators to the WAGMI subnet, and created the WAGMI chain.
- SubnetID: 28nrH5T2BMvNrWecFcV3mfccjs6axM1TVyqe79MCv2Mhs8kxiY
- ChainID: 2ebCneCbwthjQ1rYT41nhd7M76Hc6YmosMAQrTFhBq8qeqh6tt
Network ID: 11111
Chain ID: 11111
Block Gas Limit: 20,000,000 (2.5x C-Chain)
10s Gas Target: 100,000,000 (~6.67x C-Chain)
Min Fee: 1 GWei (4% of C-Chain)
Target Block Rate: 2s (Same as C-Chain)
Network Name: WAGMI
RPC URL: https://subnets.avax.network/wagmi/wagmi-chain-testnet/rpc
Chain ID: 11111
Symbol: WGM
Explorer: https://subnets.avax.network/wagmi/wagmi-chain-testnet/explorer
Address: 0x3Ee7094DADda15810F191DD6AcF7E4FFa37571e4
IPFS: /ipfs/QmVAuheeidjD2ktdX3sSHMQqSfcjtmca1g9jr7w9GQf7pU
{
"compiler": { "version": "0.5.17+commit.d19bba13" },
"language": "Solidity",
"output": {
"abi": [
{
"anonymous": false,
"inputs": [
{
"indexed": true,
"internalType": "address",
"name": "src",
"type": "address"
},
{
"indexed": true,
"internalType": "address",
"name": "guy",
"type": "address"
},
{
"indexed": false,
"internalType": "uint256",
"name": "wad",
"type": "uint256"
}
],
"name": "Approval",
"type": "event"
},
{
"anonymous": false,
"inputs": [
{
"indexed": true,
"internalType": "address",
"name": "dst",
"type": "address"
},
{
"indexed": false,
"internalType": "uint256",
"name": "wad",
"type": "uint256"
}
],
"name": "Deposit",
"type": "event"
},
{
"anonymous": false,
"inputs": [
{
"indexed": true,
"internalType": "address",
"name": "src",
"type": "address"
},
{
"indexed": true,
"internalType": "address",
"name": "dst",
"type": "address"
},
{
"indexed": false,
"internalType": "uint256",
"name": "wad",
"type": "uint256"
}
],
"name": "Transfer",
"type": "event"
},
{
"anonymous": false,
"inputs": [
{
"indexed": true,
"internalType": "address",
"name": "src",
"type": "address"
},
{
"indexed": false,
"internalType": "uint256",
"name": "wad",
"type": "uint256"
}
],
"name": "Withdrawal",
"type": "event"
},
{ "payable": true, "stateMutability": "payable", "type": "fallback" },
{
"constant": true,
"inputs": [
{ "internalType": "address", "name": "", "type": "address" },
{ "internalType": "address", "name": "", "type": "address" }
],
"name": "allowance",
"outputs": [
{ "internalType": "uint256", "name": "", "type": "uint256" }
],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"constant": false,
"inputs": [
{ "internalType": "address", "name": "guy", "type": "address" },
{ "internalType": "uint256", "name": "wad", "type": "uint256" }
],
"name": "approve",
"outputs": [{ "internalType": "bool", "name": "", "type": "bool" }],
"payable": false,
"stateMutability": "nonpayable",
"type": "function"
},
{
"constant": true,
"inputs": [
{ "internalType": "address", "name": "", "type": "address" }
],
"name": "balanceOf",
"outputs": [
{ "internalType": "uint256", "name": "", "type": "uint256" }
],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"constant": true,
"inputs": [],
"name": "decimals",
"outputs": [{ "internalType": "uint8", "name": "", "type": "uint8" }],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"constant": false,
"inputs": [],
"name": "deposit",
"outputs": [],
"payable": true,
"stateMutability": "payable",
"type": "function"
},
{
"constant": true,
"inputs": [],
"name": "name",
"outputs": [{ "internalType": "string", "name": "", "type": "string" }],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"constant": true,
"inputs": [],
"name": "symbol",
"outputs": [{ "internalType": "string", "name": "", "type": "string" }],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"constant": true,
"inputs": [],
"name": "totalSupply",
"outputs": [
{ "internalType": "uint256", "name": "", "type": "uint256" }
],
"payable": false,
"stateMutability": "view",
"type": "function"
},
{
"constant": false,
"inputs": [
{ "internalType": "address", "name": "dst", "type": "address" },
{ "internalType": "uint256", "name": "wad", "type": "uint256" }
],
"name": "transfer",
"outputs": [{ "internalType": "bool", "name": "", "type": "bool" }],
"payable": false,
"stateMutability": "nonpayable",
"type": "function"
},
{
"constant": false,
"inputs": [
{ "internalType": "address", "name": "src", "type": "address" },
{ "internalType": "address", "name": "dst", "type": "address" },
{ "internalType": "uint256", "name": "wad", "type": "uint256" }
],
"name": "transferFrom",
"outputs": [{ "internalType": "bool", "name": "", "type": "bool" }],
"payable": false,
"stateMutability": "nonpayable",
"type": "function"
},
{
"constant": false,
"inputs": [
{ "internalType": "uint256", "name": "wad", "type": "uint256" }
],
"name": "withdraw",
"outputs": [],
"payable": false,
"stateMutability": "nonpayable",
"type": "function"
}
],
"devdoc": { "methods": {} },
"userdoc": { "methods": {} }
},
"settings": {
"compilationTarget": { "contracts/wwagmi.sol": "WWAGMI" },
"evmVersion": "istanbul",
"libraries": {},
"optimizer": { "enabled": false, "runs": 200 },
"remappings": []
},
"sources": {
"contracts/wwagmi.sol": {
"keccak256": "0x0a6ce5559225d3c99db4a5e24777049df3c84886ba9a08147f23afae4261b509",
"urls": [
"bzz-raw://0aef254c65ae30b578256a7e2496ed18bf0cb68e97f5831050e17a2cf0192a7e",
"dweb:/ipfs/QmSwAbdnaYvrjDHTKnE3qBZ3smT7uipSSfSGBUiKWmNWEY"
]
}
},
"version": 1
}// Copyright (C) 2015, 2016, 2017 Dapphub
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
// Contract name, token name, and token symbol modified by Ava Labs 2020
pragma solidity >=0.4.22 <0.6;
contract WWAGMI{
string public name = "Wrapped WAGMI";
string public symbol = "WWAGMI";
uint8 public decimals = 18;
event Approval(address indexed src, address indexed guy, uint wad);
event Transfer(address indexed src, address indexed dst, uint wad);
event Deposit(address indexed dst, uint wad);
event Withdrawal(address indexed src, uint wad);
mapping (address => uint) public balanceOf;
mapping (address => mapping (address => uint)) public allowance;
function() external payable {
deposit();
}
function deposit() public payable {
balanceOf[msg.sender] += msg.value;
emit Deposit(msg.sender, msg.value);
}
function withdraw(uint wad) public {
require(balanceOf[msg.sender] >= wad);
balanceOf[msg.sender] -= wad;
msg.sender.transfer(wad);
emit Withdrawal(msg.sender, wad);
}
function totalSupply() public view returns (uint) {
return address(this).balance;
}
function approve(address guy, uint wad) public returns (bool) {
allowance[msg.sender][guy] = wad;
emit Approval(msg.sender, guy, wad);
return true;
}
function transfer(address dst, uint wad) public returns (bool) {
return transferFrom(msg.sender, dst, wad);
}
function transferFrom(address src, address dst, uint wad)
public
returns (bool)
{
require(balanceOf[src] >= wad);
if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
require(allowance[src][msg.sender] >= wad);
allowance[src][msg.sender] -= wad;
}
balanceOf[src] -= wad;
balanceOf[dst] += wad;
emit Transfer(src, dst, wad);
return true;
}
}