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solidity

# NPM
npm install -g solc

# solc by docker
docker run --rm -it ethereum/solc:stable solc --version
docker run --rm -it -v $PWD:/src ethereum/solc:stable -o /src/output --abi --bin /src/Contract.sol

# brew
brew install ethereum/ethereum/solidity

Syntax

unitvalue
wei1
gwei1e9
ether1e18
  • 时间单位 seconds, minutes, hours, days, weeks
  • block
    • basefee, chainid, coinbase, difficulty, gaslimit, number, timestamp
  • gasleft() returns (uint256)
  • blockhash(uint blockNumber) returns (bytes32)
  • msg
    • data, sender, sig, value
  • tx
    • gasprice, origin
  • abi
    • decode, encode, encodePacked, encodeWithSelector, encodeWithSignature, encodeCall
  • error
    • assert, require, revert
  • math
    • addmod, mulmod, keccak256, sha256, ripemd160, ecrecover
  • this - 当前合约地址
  • selfdestruct(address payable recipient) - 销毁合约
  • type(xyz)
    • name, creationCode, runtimeCode, interfaceId, min, max

  • pragma
  • import
  • contract
  • library
  • interface
  • 类型
    • bool - !,&&,||,==,!=
    • uint,int - <=,<,==,!=,>=,>, &,|,^,~, <<,>>, +,-.*./,%,**
      • type(int).{min,max} 类型最大最小值
      • 8,16,24,32,64,128,160,256
      • 8-256, step 8
      • uint,int -> uint256, int256
    • fixed, ufixed - MxN - M.N - 8 < M < 256, 0 < N < 80
    • address, address payable
      • bytes20, uint160
      • <address>
        • balance, code, codehash, call, delegatecall, staticcall
      • <address payable>
        • transfer
        • send
    • bytesN - 1 < N < 32
    • bytes - 动态数组
    • string - 数组
    • enum
    • valute type - type UFixed256x18 is uint256
    • modifier
      • pure,view,payable,immutable,anonymous,indexed,virtual,override
    • event
      • anonymous - 不存储事件签名作为 topic
      • indexed - 存储参数作为 topic
    • function
      • pure - 不能访问 state
      • view - 不能修改 state
      • payable - 可接受 ether
      • virtual - 可修改
      • override
      • 可见性
        • public, private, external, internal
      • <function>
        • address
        • selector
    • contract - 类似 class
    • 引用
      • memory, storage, calldata
    • mapping - 类似 map
      • key 使用 keccak256 计算 - 不存储 key 值
      • 没有长度,不能遍历
    • struct
    • delete xyz - 设置为初始值,可 删除数组/mapping 元素
  • 变量
    • 状态变量 - 位于 storage
    • 本地变量
    • 全局变量
  • 函数 - private, public, external, internal, view, pure
    • 默认 public
    • external 不能自己调用,只能给外部调用
      • 推荐使用
    • internal - 类似 protected
    • view - 只读
    • pure - 不读也不写状态变量
    • 支持自定义 modifier - 支持接受参数
      • _; 表示原始代码
  • https://docs.soliditylang.org/en/latest/types.html
  • https://docs.soliditylang.org/en/latest/units-and-global-variables.html

Interfaces

  • Ownable, CloneFactory, ECR20
// EIP-1167
interface CloneFactory {
function createClone(address target) internal returns (address result);

function isClone(address target, address query) internal view returns (bool result);
}

FAQ

_;

modifier onlyOwner {
if (msg.sender != owner) throw;
_; // 原本的代码
}

例如

function setValue(uint256 _val) onlyOwner {
value = _val;
}

变成

function setValue(uint256 _val) {
if (msg.sender != owner) throw;
value = _val;
}

Stack too deep when compiling inline assembly

EVM 只有 16 slots, 尝试将 storage 移到 memory

或者设置 optimizer

const config: HardhatUserConfig = {
solidity: {
version: '0.8.4',
settings: {
optimizer: {
runs: 200,
enabled: true,
},
},
},
};
export default config;

Type struct Moloch.Proposal is only valid in storage because it contains a (nested) mapping

struct 包含 mapping,不能使用 memory,使用 storage