Vyper language preview

1. Token contract

decorators, types, and events

horizon-dark

# @version 0.3.10

balances: public(HashMap[address, uint256])

event Transfer:
    sender: indexed(address)
    receiver: indexed(address)
    amount: uint256

@external
def transfer(to: address, amount: uint256) -> bool:
    assert self.balances[msg.sender] >= amount, "insufficient balance"
    self.balances[msg.sender] -= amount
    self.balances[to] += amount
    log Transfer(msg.sender, to, amount)
    return True

atom-one-dark

# @version 0.3.10

balances: public(HashMap[address, uint256])

event Transfer:
    sender: indexed(address)
    receiver: indexed(address)
    amount: uint256

@external
def transfer(to: address, amount: uint256) -> bool:
    assert self.balances[msg.sender] >= amount, "insufficient balance"
    self.balances[msg.sender] -= amount
    self.balances[to] += amount
    log Transfer(msg.sender, to, amount)
    return True

github-dark

# @version 0.3.10

balances: public(HashMap[address, uint256])

event Transfer:
    sender: indexed(address)
    receiver: indexed(address)
    amount: uint256

@external
def transfer(to: address, amount: uint256) -> bool:
    assert self.balances[msg.sender] >= amount, "insufficient balance"
    self.balances[msg.sender] -= amount
    self.balances[to] += amount
    log Transfer(msg.sender, to, amount)
    return True

dracula

# @version 0.3.10

balances: public(HashMap[address, uint256])

event Transfer:
    sender: indexed(address)
    receiver: indexed(address)
    amount: uint256

@external
def transfer(to: address, amount: uint256) -> bool:
    assert self.balances[msg.sender] >= amount, "insufficient balance"
    self.balances[msg.sender] -= amount
    self.balances[to] += amount
    log Transfer(msg.sender, to, amount)
    return True

nord

# @version 0.3.10

balances: public(HashMap[address, uint256])

event Transfer:
    sender: indexed(address)
    receiver: indexed(address)
    amount: uint256

@external
def transfer(to: address, amount: uint256) -> bool:
    assert self.balances[msg.sender] >= amount, "insufficient balance"
    self.balances[msg.sender] -= amount
    self.balances[to] += amount
    log Transfer(msg.sender, to, amount)
    return True

github

# @version 0.3.10

balances: public(HashMap[address, uint256])

event Transfer:
    sender: indexed(address)
    receiver: indexed(address)
    amount: uint256

@external
def transfer(to: address, amount: uint256) -> bool:
    assert self.balances[msg.sender] >= amount, "insufficient balance"
    self.balances[msg.sender] -= amount
    self.balances[to] += amount
    log Transfer(msg.sender, to, amount)
    return True

2. View functions

constants, immutables, and internal helpers

horizon-dark

MAX_SUPPLY: constant(uint256) = 1_000_000
owner: immutable(address)

@deploy
def __init__():
    owner = msg.sender

@view
@external
def is_owner(account: address) -> bool:
    return account == owner

atom-one-dark

MAX_SUPPLY: constant(uint256) = 1_000_000
owner: immutable(address)

@deploy
def __init__():
    owner = msg.sender

@view
@external
def is_owner(account: address) -> bool:
    return account == owner

github-dark

MAX_SUPPLY: constant(uint256) = 1_000_000
owner: immutable(address)

@deploy
def __init__():
    owner = msg.sender

@view
@external
def is_owner(account: address) -> bool:
    return account == owner

dracula

MAX_SUPPLY: constant(uint256) = 1_000_000
owner: immutable(address)

@deploy
def __init__():
    owner = msg.sender

@view
@external
def is_owner(account: address) -> bool:
    return account == owner

nord

MAX_SUPPLY: constant(uint256) = 1_000_000
owner: immutable(address)

@deploy
def __init__():
    owner = msg.sender

@view
@external
def is_owner(account: address) -> bool:
    return account == owner

github

MAX_SUPPLY: constant(uint256) = 1_000_000
owner: immutable(address)

@deploy
def __init__():
    owner = msg.sender

@view
@external
def is_owner(account: address) -> bool:
    return account == owner

3. Byte strings

b"..." literal prefix

horizon-dark

SELECTOR: constant(bytes4) = b"\x01\x02\x03\x04"

@external
@pure
def matches(sig: bytes4) -> bool:
    return sig == SELECTOR

atom-one-dark

SELECTOR: constant(bytes4) = b"\x01\x02\x03\x04"

@external
@pure
def matches(sig: bytes4) -> bool:
    return sig == SELECTOR

github-dark

SELECTOR: constant(bytes4) = b"\x01\x02\x03\x04"

@external
@pure
def matches(sig: bytes4) -> bool:
    return sig == SELECTOR

dracula

SELECTOR: constant(bytes4) = b"\x01\x02\x03\x04"

@external
@pure
def matches(sig: bytes4) -> bool:
    return sig == SELECTOR

nord

SELECTOR: constant(bytes4) = b"\x01\x02\x03\x04"

@external
@pure
def matches(sig: bytes4) -> bool:
    return sig == SELECTOR

github

SELECTOR: constant(bytes4) = b"\x01\x02\x03\x04"

@external
@pure
def matches(sig: bytes4) -> bool:
    return sig == SELECTOR