Curve DAO Token (CRV)
The Curve DAO Token (CRV) is the protocol's governance token. It is based on the ERC-20 token standard as defined at EIP-20.
CRV.vyThe source code for the CRV.vy contract can be found on GitHub. The contract is written using Vyper version 0.2.4.
The token is deployed on 
Ethereum at 0xD533a949740bb3306d119CC777fa900bA034cd52.
{ }Contract ABI▼
[{"name":"Transfer","inputs":[{"type":"address","name":"_from","indexed":true},{"type":"address","name":"_to","indexed":true},{"type":"uint256","name":"_value","indexed":false}],"anonymous":false,"type":"event"},{"name":"Approval","inputs":[{"type":"address","name":"_owner","indexed":true},{"type":"address","name":"_spender","indexed":true},{"type":"uint256","name":"_value","indexed":false}],"anonymous":false,"type":"event"},{"name":"UpdateMiningParameters","inputs":[{"type":"uint256","name":"time","indexed":false},{"type":"uint256","name":"rate","indexed":false},{"type":"uint256","name":"supply","indexed":false}],"anonymous":false,"type":"event"},{"name":"SetMinter","inputs":[{"type":"address","name":"minter","indexed":false}],"anonymous":false,"type":"event"},{"name":"SetAdmin","inputs":[{"type":"address","name":"admin","indexed":false}],"anonymous":false,"type":"event"},{"outputs":[],"inputs":[{"type":"string","name":"_name"},{"type":"string","name":"_symbol"},{"type":"uint256","name":"_decimals"}],"stateMutability":"nonpayable","type":"constructor"},{"name":"update_mining_parameters","outputs":[],"inputs":[],"stateMutability":"nonpayable","type":"function","gas":148748},{"name":"start_epoch_time_write","outputs":[{"type":"uint256","name":""}],"inputs":[],"stateMutability":"nonpayable","type":"function","gas":149603},{"name":"future_epoch_time_write","outputs":[{"type":"uint256","name":""}],"inputs":[],"stateMutability":"nonpayable","type":"function","gas":149806},{"name":"available_supply","outputs":[{"type":"uint256","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":4018},{"name":"mintable_in_timeframe","outputs":[{"type":"uint256","name":""}],"inputs":[{"type":"uint256","name":"start"},{"type":"uint256","name":"end"}],"stateMutability":"view","type":"function","gas":2216141},{"name":"set_minter","outputs":[],"inputs":[{"type":"address","name":"_minter"}],"stateMutability":"nonpayable","type":"function","gas":38698},{"name":"set_admin","outputs":[],"inputs":[{"type":"address","name":"_admin"}],"stateMutability":"nonpayable","type":"function","gas":37837},{"name":"totalSupply","outputs":[{"type":"uint256","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":1421},{"name":"allowance","outputs":[{"type":"uint256","name":""}],"inputs":[{"type":"address","name":"_owner"},{"type":"address","name":"_spender"}],"stateMutability":"view","type":"function","gas":1759},{"name":"transfer","outputs":[{"type":"bool","name":""}],"inputs":[{"type":"address","name":"_to"},{"type":"uint256","name":"_value"}],"stateMutability":"nonpayable","type":"function","gas":75139},{"name":"transferFrom","outputs":[{"type":"bool","name":""}],"inputs":[{"type":"address","name":"_from"},{"type":"address","name":"_to"},{"type":"uint256","name":"_value"}],"stateMutability":"nonpayable","type":"function","gas":111433},{"name":"approve","outputs":[{"type":"bool","name":""}],"inputs":[{"type":"address","name":"_spender"},{"type":"uint256","name":"_value"}],"stateMutability":"nonpayable","type":"function","gas":39288},{"name":"mint","outputs":[{"type":"bool","name":""}],"inputs":[{"type":"address","name":"_to"},{"type":"uint256","name":"_value"}],"stateMutability":"nonpayable","type":"function","gas":228030},{"name":"burn","outputs":[{"type":"bool","name":""}],"inputs":[{"type":"uint256","name":"_value"}],"stateMutability":"nonpayable","type":"function","gas":74999},{"name":"set_name","outputs":[],"inputs":[{"type":"string","name":"_name"},{"type":"string","name":"_symbol"}],"stateMutability":"nonpayable","type":"function","gas":178270},{"name":"name","outputs":[{"type":"string","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":8063},{"name":"symbol","outputs":[{"type":"string","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":7116},{"name":"decimals","outputs":[{"type":"uint256","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":1721},{"name":"balanceOf","outputs":[{"type":"uint256","name":""}],"inputs":[{"type":"address","name":"arg0"}],"stateMutability":"view","type":"function","gas":1905},{"name":"minter","outputs":[{"type":"address","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":1781},{"name":"admin","outputs":[{"type":"address","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":1811},{"name":"mining_epoch","outputs":[{"type":"int128","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":1841},{"name":"start_epoch_time","outputs":[{"type":"uint256","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":1871},{"name":"rate","outputs":[{"type":"uint256","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":1901}]
For a broader understanding of the use case of the CRV token, check out Understanding CRV.
Transfer and Allowance
approve
CRV.approve(_spender: address, _value: uint256) -> boolApproval may only be from zero -> nonzero or from nonzero -> zero in order to mitigate the potential race condition described here: https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
Function to approve _spender to transfer _value tokens on behalf of msg.sender.
Returns: true (bool).
Emits: Approval event.
| Input | Type | Description |
|---|---|---|
_spender | address | Spender address |
_value | uint256 | Amount to approve |
<>Source code▼
event Approval:
_owner: indexed(address)
_spender: indexed(address)
_value: uint256
allowances: HashMap[address, HashMap[address, uint256]]
@external
def approve(_spender : address, _value : uint256) -> bool:
"""
@notice Approve `_spender` to transfer `_value` tokens on behalf of `msg.sender`
@dev Approval may only be from zero -> nonzero or from nonzero -> zero in order
to mitigate the potential race condition described here:
https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
@param _spender The address which will spend the funds
@param _value The amount of tokens to be spent
@return bool success
"""
assert _value == 0 or self.allowances[msg.sender][_spender] == 0
self.allowances[msg.sender][_spender] = _value
log Approval(msg.sender, _spender, _value)
return True
▶Example▼
This example approves 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 to transfer 1 CRV token on behalf of msg.sender.
>>> CRV.approve('0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045', 1000000000000000000)
'True'
allowance
CRV.allowance(_owner: address, _spender: address) -> uint256: viewGetter method to check the amount of tokens that _owner has allowed _spender to use.
Returns: amount of tokens (uint256) that _owner has allowed _spender to use.
| Input | Type | Description |
|---|---|---|
_owner | address | Owner address |
_spender | address | Spender address |
<>Source code▼
allowances: HashMap[address, HashMap[address, uint256]]
@external
@view
def allowance(_owner : address, _spender : address) -> uint256:
"""
@notice Check the amount of tokens that an owner allowed to a spender
@param _owner The address which owns the funds
@param _spender The address which will spend the funds
@return uint256 specifying the amount of tokens still available for the spender
"""
return self.allowances[_owner][_spender]
▶Example▼
This example returns the amount of CRV tokens that 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 is allowed to spend on behalf of 0x7a16fF8270133F063aAb6C9977183D9e72835428.
>>> CRV.allowance('0x7a16fF8270133F063aAb6C9977183D9e72835428', '0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045')
0
transfer
CRV.transfer(_to: address, _value: uint256) -> boolVyper does not allow underflows; thus, any subtraction in this function will revert if there is an insufficient balance.
Additionally, transfers to ZERO_ADDRESS are not allowed.
Function to transfer _value tokens from msg.sender to _to.
Returns: true (bool).
Emits: Transfer event.
| Input | Type | Description |
|---|---|---|
_to | address | Receiver address of the tokens |
_value | uint256 | Amount of tokens to transfer |
<>Source code▼
event Transfer:
_from: indexed(address)
_to: indexed(address)
_value: uint256
balanceOf: public(HashMap[address, uint256])
@external
def transfer(_to : address, _value : uint256) -> bool:
"""
@notice Transfer `_value` tokens from `msg.sender` to `_to`
@dev Vyper does not allow underflows, so the subtraction in
this function will revert on an insufficient balance
@param _to The address to transfer to
@param _value The amount to be transferred
@return bool success
"""
assert _to != ZERO_ADDRESS # dev: transfers to 0x0 are not allowed
self.balanceOf[msg.sender] -= _value
self.balanceOf[_to] += _value
log Transfer(msg.sender, _to, _value)
return True
▶Example▼
This example transfers 1 CRV token from msg.sender to 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045.
>>> CRV.transfer('0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045', 1000000000000000000)
'True'
transferFrom
CRV.transferFrom(_from: address, _to: address, _value: uint256) -> boolVyper does not allow underflows; thus, any subtraction in this function will revert if there is an insufficient balance.
Additionally, transfers to ZERO_ADDRESS are not allowed.
Function to transfer _value tokens from _from to _to.
Returns: true (bool).
Emits: Transfer event.
| Input | Type | Description |
|---|---|---|
_from | address | Address to send tokens from |
_to | address | Receiver address of the tokens |
_value | uint256 | Amount of tokens to transfer |
<>Source code▼
event Transfer:
_from: indexed(address)
_to: indexed(address)
_value: uint256
balanceOf: public(HashMap[address, uint256])
allowances: HashMap[address, HashMap[address, uint256]]
@external
def transferFrom(_from : address, _to : address, _value : uint256) -> bool:
"""
@notice Transfer `_value` tokens from `_from` to `_to`
@param _from address The address which you want to send tokens from
@param _to address The address which you want to transfer to
@param _value uint256 the amount of tokens to be transferred
@return bool success
"""
assert _to != ZERO_ADDRESS # dev: transfers to 0x0 are not allowed
# NOTE: vyper does not allow underflows
# so the following subtraction would revert on insufficient balance
self.balanceOf[_from] -= _value
self.balanceOf[_to] += _value
self.allowances[_from][msg.sender] -= _value
log Transfer(_from, _to, _value)
return True
▶Example▼
This example transfers 1 CRV token from 0x7a16fF8270133F063aAb6C9977183D9e72835428 to 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045.
>>> CRV.transferFrom('0x7a16fF8270133F063aAb6C9977183D9e72835428', '0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045', 1000000000000000000)
'True'
Emissions, Minting and Burning
Curve has a strict minting mechanism of new CRV tokens. New tokens are minted based on the gauge weights of an epoch. For more information, see Gauge Weight Voting
New CRV tokens can only be minted by the minter contract.
Mining parameters are used to determine token emissions, which are based on epochs (one year). With each passing epoch, the rate will be reduced, consequently decreasing the overall CRV emissions.
The rate can be adjusted by invoking the update_mining_parameters() function. Although this function is accessible to anyone, attempts to call it will be reverted if a year has not elapsed since the last update. When successfully executed, the mining_epoch increments by 1, and the start_epoch_time updates to the timestamp of the function call. Furthermore, the update_mining_parameters() function will automatically trigger if someone attempts to mint CRV before a scheduled rate reduction.
Effectively, each rate reduction decreases CRV inflation by approximately 15.9%. The future rate is calculated as follows:
with fetched from the rate() function.
minter
CRV.minter() -> address: viewGetter for the Minter contract address. The minter address can only be set once (at deployment) and not altered after.
Returns: Minter contract (address).
<>Source code▼
minter: public(address)
▶Example▼
This example returns the minter contract address.
>>> CRV.minter()
'0xd061D61a4d941c39E5453435B6345Dc261C2fcE0'
mint
CRV.mint(_to: address, _value: uint256) -> boolThis function is only callable by the Minter contract.
Function to mint _value tokens and assign them to _to.
Returns: true (bool).
Emits: Transfer event.
| Input | Type | Description |
|---|---|---|
_to | address | Receiver of the minted tokens |
_value | uint256 | Amount to mint |
<>Source code▼
event Transfer:
_from: indexed(address)
_to: indexed(address)
_value: uint256
minter: public(address)
balanceOf: public(HashMap[address, uint256])
total_supply: uint256
@external
def mint(_to: address, _value: uint256) -> bool:
"""
@notice Mint `_value` tokens and assign them to `_to`
@dev Emits a Transfer event originating from 0x00
@param _to The account that will receive the created tokens
@param _value The amount that will be created
@return bool success
"""
assert msg.sender == self.minter # dev: minter only
assert _to != ZERO_ADDRESS # dev: zero address
if block.timestamp >= self.start_epoch_time + RATE_REDUCTION_TIME:
self._update_mining_parameters()
_total_supply: uint256 = self.total_supply + _value
assert _total_supply <= self._available_supply() # dev: exceeds allowable mint amount
self.total_supply = _total_supply
self.balanceOf[_to] += _value
log Transfer(ZERO_ADDRESS, _to, _value)
return True
▶Example▼
This example mints 1 CRV token to 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045.
>>> CRV.mint('0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045', 1000000000000000000)
'True'
mintable_in_timeframe
CRV.mintable_in_timeframe(start: uint256, end: uint256) -> uint256: viewGetter for the mintable supply between start and end timestamps. The value is dependent on the current emission rate of the token.
Returns: mintable tokens (uint256).
| Input | Type | Description |
|---|---|---|
start | uint256 | Start timestamp |
end | uint256 | End timestamp |
<>Source code▼
@external
@view
def mintable_in_timeframe(start: uint256, end: uint256) -> uint256:
"""
@notice How much supply is mintable from start timestamp till end timestamp
@param start Start of the time interval (timestamp)
@param end End of the time interval (timestamp)
@return Tokens mintable from `start` till `end`
"""
assert start <= end # dev: start > end
to_mint: uint256 = 0
current_epoch_time: uint256 = self.start_epoch_time
current_rate: uint256 = self.rate
# Special case if end is in future (not yet minted) epoch
if end > current_epoch_time + RATE_REDUCTION_TIME:
current_epoch_time += RATE_REDUCTION_TIME
current_rate = current_rate * RATE_DENOMINATOR / RATE_REDUCTION_COEFFICIENT
assert end <= current_epoch_time + RATE_REDUCTION_TIME # dev: too far in future
for i in range(999): # Curve will not work in 1000 years. Darn!
if end >= current_epoch_time:
current_end: uint256 = end
if current_end > current_epoch_time + RATE_REDUCTION_TIME:
current_end = current_epoch_time + RATE_REDUCTION_TIME
current_start: uint256 = start
if current_start >= current_epoch_time + RATE_REDUCTION_TIME:
break # We should never get here but what if...
elif current_start < current_epoch_time:
current_start = current_epoch_time
to_mint += current_rate * (current_end - current_start)
if start >= current_epoch_time:
break
current_epoch_time -= RATE_REDUCTION_TIME
current_rate = current_rate * RATE_REDUCTION_COEFFICIENT / RATE_DENOMINATOR # double-division with rounding made rate a bit less => good
assert current_rate <= INITIAL_RATE # This should never happen
return to_mint
▶Example▼
This example returns the mintable CRV supply between two timestamps (1704067200 to 1704153600).
>>> CRV.mintable_in_timeframe(1704067200, 1704153600)
573744014880952380952380
burn
CRV.burn(_value: uint256) -> boolFunction to burn _value tokens of the function caller by sending them to ZERO_ADDRESS.
Returns: true (bool).
Emits: Transfer event.
| Input | Type | Description |
|---|---|---|
_value | uint256 | Amount of tokens to burn |
<>Source code▼
event Transfer:
_from: indexed(address)
_to: indexed(address)
_value: uint256
balanceOf: public(HashMap[address, uint256])
total_supply: uint256
@external
def burn(_value: uint256) -> bool:
"""
@notice Burn `_value` tokens belonging to `msg.sender`
@dev Emits a Transfer event with a destination of 0x00
@param _value The amount that will be burned
@return bool success
"""
self.balanceOf[msg.sender] -= _value
self.total_supply -= _value
log Transfer(msg.sender, ZERO_ADDRESS, _value)
return True
▶Example▼
This example burns 1 CRV token belonging to msg.sender.
>>> CRV.burn(1000000000000000000)
'True'
mining_epoch
CRV.mining_epoch() -> int128: viewGetter for the current mining epoch. The mining epoch is incremented by 1 every time update_mining_parameters() is successfully called. At deployment, mining_epoch was set to -1.
Returns: mining epoch (int128).
<>Source code▼
mining_epoch: public(int128)
@external
def __init__(_name: String[64], _symbol: String[32], _decimals: uint256):
"""
@notice Contract constructor
@param _name Token full name
@param _symbol Token symbol
@param _decimals Number of decimals for token
"""
...
self.mining_epoch = -1
...
@internal
def _update_mining_parameters():
"""
@dev Update mining rate and supply at the start of the epoch
Any modifying mining call must also call this
"""
_rate: uint256 = self.rate
_start_epoch_supply: uint256 = self.start_epoch_supply
self.start_epoch_time += RATE_REDUCTION_TIME
self.mining_epoch += 1
if _rate == 0:
_rate = INITIAL_RATE
else:
_start_epoch_supply += _rate * RATE_REDUCTION_TIME
self.start_epoch_supply = _start_epoch_supply
_rate = _rate * RATE_DENOMINATOR / RATE_REDUCTION_COEFFICIENT
self.rate = _rate
log UpdateMiningParameters(block.timestamp, _rate, _start_epoch_supply)
▶Example▼
This example returns the current mining epoch. The value is fetched live from the blockchain.
start_epoch_time
CRV.start_epoch_time() -> uint256: viewGetter for the start timestamp of the current mining epoch.
Returns: timestamp (uint256).
<>Source code▼
start_epoch_time: public(uint256)
@external
def __init__(_name: String[64], _symbol: String[32], _decimals: uint256):
"""
@notice Contract constructor
@param _name Token full name
@param _symbol Token symbol
@param _decimals Number of decimals for token
"""
...
self.start_epoch_time = block.timestamp + INFLATION_DELAY - RATE_REDUCTION_TIME
...
▶Example▼
This example returns the start timestamp of the current mining epoch. The value is fetched live from the blockchain.
rate
CRV.rate() -> uint256: viewGetter for the current inflation rate of the CRV token emission. The rate is denominated in emissions per second and has a base of 1e18.
To calculate the CRV emission per day:
Returns: current inflation rate (uint256).
<>Source code▼
rate: public(uint256)
▶Example▼
This example returns the current CRV emission rate per second. The value is fetched live from the blockchain.
update_mining_parameters
CRV.update_mining_parameters()Function to update the mining parameters for the token. By updating, the newly decreased inflation rate is applied. This function is callable by anyone. However, the call will revert if block.timestamp is less than or equal to start_epoch_time + RATE_REDUCTION_TIME, indicating that one year has not yet passed and therefore the rate cannot be updated yet.
Emits: UpdateMiningParameters event.
<>Source code▼
event UpdateMiningParameters:
time: uint256
rate: uint256
supply: uint256
YEAR: constant(uint256) = 86400 * 365
# Supply parameters
INITIAL_SUPPLY: constant(uint256) = 1_303_030_303
INITIAL_RATE: constant(uint256) = 274_815_283 * 10 **18 / YEAR # leading to 43% premine
RATE_REDUCTION_TIME: constant(uint256) = YEAR
RATE_REDUCTION_COEFFICIENT: constant(uint256) = 1189207115002721024 # 2 **(1/4) * 1e18
RATE_DENOMINATOR: constant(uint256) = 10 **18
INFLATION_DELAY: constant(uint256) = 86400
# Supply variables
mining_epoch: public(int128)
start_epoch_time: public(uint256)
rate: public(uint256)
start_epoch_supply: uint256
@external
def update_mining_parameters():
"""
@notice Update mining rate and supply at the start of the epoch
@dev Callable by any address, but only once per epoch
Total supply becomes slightly larger if this function is called late
"""
assert block.timestamp >= self.start_epoch_time + RATE_REDUCTION_TIME # dev: too soon!
self._update_mining_parameters()
@internal
def _update_mining_parameters():
"""
@dev Update mining rate and supply at the start of the epoch
Any modifying mining call must also call this
"""
_rate: uint256 = self.rate
_start_epoch_supply: uint256 = self.start_epoch_supply
self.start_epoch_time += RATE_REDUCTION_TIME
self.mining_epoch += 1
if _rate == 0:
_rate = INITIAL_RATE
else:
_start_epoch_supply += _rate * RATE_REDUCTION_TIME
self.start_epoch_supply = _start_epoch_supply
_rate = _rate * RATE_DENOMINATOR / RATE_REDUCTION_COEFFICIENT
self.rate = _rate
log UpdateMiningParameters(block.timestamp, _rate, _start_epoch_supply)
▶Example▼
This example updates the mining parameters for the CRV token, applying the newly decreased inflation rate.
>>> CRV.update_mining_parameters()
start_epoch_time_write
CRV.start_epoch_time_write() -> uint256Function to get the current mining epoch start while simultaneously updating mining parameters if possible. If updating is not possible, the function will only return the start timestamp of the current epoch.
Returns: start timestamp of the epoch (uint256).
<>Source code▼
start_epoch_time: public(uint256)
@external
def start_epoch_time_write() -> uint256:
"""
@notice Get timestamp of the current mining epoch start
while simultaneously updating mining parameters
@return Timestamp of the epoch
"""
_start_epoch_time: uint256 = self.start_epoch_time
if block.timestamp >= _start_epoch_time + RATE_REDUCTION_TIME:
self._update_mining_parameters()
return self.start_epoch_time
else:
return _start_epoch_time
▶Example▼
This example returns the current epoch start timestamp while updating mining parameters if applicable.
>>> CRV.start_epoch_time_write()
1691625600
future_epoch_time_write
CRV.future_epoch_time_write() -> uint256Function to get the next mining epoch start timestamp while simultaneously updating mining parameters if possible. If updating is not possible, the function will only return the start timestamp of the future epoch.
Returns: start timestamp of the future epoch (uint256).
<>Source code▼
@external
def future_epoch_time_write() -> uint256:
"""
@notice Get timestamp of the next mining epoch start
while simultaneously updating mining parameters
@return Timestamp of the next epoch
"""
_start_epoch_time: uint256 = self.start_epoch_time
if block.timestamp >= _start_epoch_time + RATE_REDUCTION_TIME:
self._update_mining_parameters()
return self.start_epoch_time + RATE_REDUCTION_TIME
else:
return _start_epoch_time + RATE_REDUCTION_TIME
▶Example▼
This example returns the next epoch start timestamp while updating mining parameters if applicable.
>>> CRV.future_epoch_time_write()
1723161600
Admin Controls and Other Methods
The controls over the Curve DAO Token are strictly limited. The admin of the contract can only modify the name, admin, or minter1.
Since the CurveOwnershipAgent is the current admin of the contract, any changes to these parameters would require a successfully passed DAO vote.
admin
CRV.admin() -> address: viewGetter for the current admin of the contract.
Returns: admin (address).
<>Source code▼
admin: public(address)
@external
def __init__(_name: String[64], _symbol: String[32], _decimals: uint256):
"""
@notice Contract constructor
@param _name Token full name
@param _symbol Token symbol
@param _decimals Number of decimals for token
"""
...
self.admin = msg.sender
...
▶Example▼
This example returns the current admin of the CRV token contract.
>>> CRV.admin()
'0x40907540d8a6C65c637785e8f8B742ae6b0b9968'
set_admin
CRV.set_admin(_admin: address)This function is only callable by the admin of the contract.
Function to change the admin of the contract.
Emits: SetAdmin event.
| Input | Type | Description |
|---|---|---|
_admin | address | New Admin Address |
<>Source code▼
event SetAdmin:
admin: address
admin: public(address)
@external
def set_admin(_admin: address):
"""
@notice Set the new admin.
@dev After all is set up, admin only can change the token name
@param _admin New admin address
"""
assert msg.sender == self.admin # dev: admin only
self.admin = _admin
log SetAdmin(_admin)
▶Example▼
This example sets a new admin for the CRV token contract.
>>> CRV.set_admin("0x0000000000000000000000000000000000000000")
name
CRV.name() -> String[64]: viewGetter for the name of the token. Name of the token can be changed by calling the set_name function.
Returns: token name (String[64]).
<>Source code▼
name: public(String[64])
@external
def __init__(_name: String[64], _symbol: String[32], _decimals: uint256):
"""
@notice Contract constructor
@param _name Token full name
@param _symbol Token symbol
@param _decimals Number of decimals for token
"""
init_supply: uint256 = INITIAL_SUPPLY * 10 **_decimals
self.name = _name
...
▶Example▼
This example returns the name of the CRV token.
>>> CRV.name()
'Curve DAO Token'
symbol
CRV.symbol() -> String[32]: viewGetter of the token symbol. Symbol of the token can be changed by calling the set_name function.
Returns: token symbol (String[32]).
<>Source code▼
symbol: public(String[32])
@external
def __init__(_name: String[64], _symbol: String[32], _decimals: uint256):
"""
@notice Contract constructor
@param _name Token full name
@param _symbol Token symbol
@param _decimals Number of decimals for token
"""
...
self.symbol = _symbol
...
▶Example▼
This example returns the symbol of the CRV token.
>>> CRV.symbol()
'CRV'
set_name
CRV.set_name(_name: String[64], _symbol: String[32])This function is only callable by the admin of the contract.
Function to change the token name and symbol.
| Input | Type | Description |
|---|---|---|
_name | String[64] | New token name. |
_symbol | String[32] | New token symbol. |
<>Source code▼
name: public(String[64])
symbol: public(String[32])
@external
def set_name(_name: String[64], _symbol: String[32]):
"""
@notice Change the token name and symbol to `_name` and `_symbol`
@dev Only callable by the admin account
@param _name New token name
@param _symbol New token symbol
"""
assert msg.sender == self.admin, "Only admin is allowed to change name"
self.name = _name
self.symbol = _symbol
▶Example▼
This example changes the name and symbol of the CRV token.
>>> CRV.set_name("New Name", "New Symbol")
set_minter
CRV.set_minter(_minter: address)minter contract is not possible anymore!This function was only utilized during the initial deployment of the Curve DAO Token. The code permits setting the minter exclusively when the current minter is ZERO_ADDRESS, a condition met solely at the time of deployment. Consequently, the minter variable could only be set once and cannot be changed thereafter.
This function is only callable by the admin of the contract.
Function to set the minter contract for the token.
Emits: SetMinter event.
| Input | Type | Description |
|---|---|---|
_minter | address | Minter contract address |
<>Source code▼
event SetMinter:
minter: address
minter: public(address)
@external
def set_minter(_minter: address):
"""
@notice Set the minter address
@dev Only callable once, when minter has not yet been set
@param _minter Address of the minter
"""
assert msg.sender == self.admin # dev: admin only
assert self.minter == ZERO_ADDRESS # dev: can set the minter only once, at creation
self.minter = _minter
log SetMinter(_minter)
▶Example▼
This example attempts to set the minter contract address. Since the minter is already set, this call will revert.
>>> CRV.set_minter("0x0000000000000000000000000000000000000000")
available_supply
CRV.available_supply() -> uint256: viewGetter for the current number of CRV tokens - claimed or unclaimed - in existence.
Returns: currently existing tokens (uint256).
<>Source code▼
@internal
@view
def _available_supply() -> uint256:
return self.start_epoch_supply + (block.timestamp - self.start_epoch_time) * self.rate
@external
@view
def available_supply() -> uint256:
"""
@notice Current number of tokens in existence (claimed or unclaimed)
"""
return self._available_supply()
▶Example▼
This example returns the current available supply of CRV tokens. The value is fetched live from the blockchain.
totalSupply
CRV.totalSupply() -> uint256: viewGetter for the total number of tokens in existence.
Returns: total supply (uint256).
<>Source code▼
total_supply: uint256
@external
@view
def totalSupply() -> uint256:
"""
@notice Total number of tokens in existence.
"""
return self.total_supply
▶Example▼
This example returns the total supply of CRV tokens. The value is fetched live from the blockchain.
decimals
CRV.decimals() -> uint256: viewGetter of the decimals of the token.
Returns: decimals (uint256).
<>Source code▼
decimals: public(uint256)
@external
def __init__(_name: String[64], _symbol: String[32], _decimals: uint256):
"""
@notice Contract constructor
@param _name Token full name
@param _symbol Token symbol
@param _decimals Number of decimals for token
"""
...
self.decimals = _decimals
...
▶Example▼
This example returns the number of decimals of the CRV token.
>>> CRV.decimals()
18
balanceOf
CRV.balanceOf(arg0: address) -> uint256: viewGetter for the CRV token balance of a specific address.
Returns: balance (uint256).
| Input | Type | Description |
|---|---|---|
arg0 | address | Wallet to check CRV balance for |
<>Source code▼
balanceOf: public(HashMap[address, uint256])
▶Example▼
This example returns the CRV token balance for a given address. Enter an address and click Query to fetch the value live from the blockchain.