合同工厂

在有关SmartPy的公告中,讨论非常简洁.> https://medium.com/@SmartPy_io/introducing-smartpy-and-smartpy-io-d4013bee7d4e#15ee .

想法是要有一个包含big_map的合同,并且big_map的每个元素都代表一个合同.

这绝对不限于SmartPy,它可以直接在Michelson,Liquidity或Fi中使用.

此主题也出现在这里: 什么是BigMap容器及其重要性?

There is a very succinct discussion in the announcement for SmartPy https://medium.com/@SmartPy_io/introducing-smartpy-and-smartpy-io-d4013bee7d4e#15ee.

The idea is to have a contract that holds a big_map and each element of the big_map represents a contract.

This is absolutely not restricted to SmartPy and it is directly doable in Michelson, Liquidity or Fi.

This subject also appeared here: What is the BigMap container and why does it matter?

这是处理流动资金的合同示例.编写仅在执行结束时才能利用远程过程调用的函数就有一个独特的挑战:

 type plus_storage = {
    count: nat,
    plus_owner: address,
  };

contract PlusOne = {
  type storage = plus_storage;
  let%init storage = (y: nat) => {
    count: y,
    plus_owner: Current.sender(),
  };
  let%entry main = (p: nat, storage) => {
    if (Current.sender() != storage.plus_owner) {
      failwith("invalid caller");
    };
    ([], storage);
  }
};

type storage = {
  owner: key,
  pl: address,
};

let%init storage = (contract_owner: key) => {
  owner: contract_owner,
  pl: KT1111111111111111111111111111111111,
}

let%entry other = (param: nat, storage) => {
  let t: option(PlusOne.instance) = Contract.at(storage.pl);
  let t = switch(t) {
    | None => Current.failwith()
    | Some(inst) => inst
  };
  let op = Contract.call(
    ~dest=t,
    ~amount=0tz,
    ~entry=main,
    ~parameter=param);
  ([op], storage);
};

let%entry main = ((), storage) => {
  let manager = Crypto.hash_key(storage.owner);
  let delegate = Some(manager);
  let spendable = false;
  let amount = Current.amount();
  let init_value: nat = 0;

  let (c_op, c_addr) =
    Contract.create(
      ~manager,
      ~delegate,
      ~spendable,
      ~delegatable=false,
      ~amount,
      ~storage={count: init_value, plus_owner: Contract.address(Contract.self())},
      (contract PlusOne),
    );

  let storage = storage.pl = c_addr;
  ([c_op], storage);
};
 

这使我想知道这是否会导致诸如"订购"和"提货"之类的终点,即餐馆.

Here's an example of a contract handling this in liquidity. There's the unique challenge of writing functions that can only utilize remote procedure calls at the end of their execution:

type plus_storage = {
    count: nat,
    plus_owner: address,
  };

contract PlusOne = {
  type storage = plus_storage;
  let%init storage = (y: nat) => {
    count: y,
    plus_owner: Current.sender(),
  };
  let%entry main = (p: nat, storage) => {
    if (Current.sender() != storage.plus_owner) {
      failwith("invalid caller");
    };
    ([], storage);
  }
};

type storage = {
  owner: key,
  pl: address,
};

let%init storage = (contract_owner: key) => {
  owner: contract_owner,
  pl: KT1111111111111111111111111111111111,
}

let%entry other = (param: nat, storage) => {
  let t: option(PlusOne.instance) = Contract.at(storage.pl);
  let t = switch(t) {
    | None => Current.failwith()
    | Some(inst) => inst
  };
  let op = Contract.call(
    ~dest=t,
    ~amount=0tz,
    ~entry=main,
    ~parameter=param);
  ([op], storage);
};

let%entry main = ((), storage) => {
  let manager = Crypto.hash_key(storage.owner);
  let delegate = Some(manager);
  let spendable = false;
  let amount = Current.amount();
  let init_value: nat = 0;

  let (c_op, c_addr) =
    Contract.create(
      ~manager,
      ~delegate,
      ~spendable,
      ~delegatable=false,
      ~amount,
      ~storage={count: init_value, plus_owner: Contract.address(Contract.self())},
      (contract PlusOne),
    );

  let storage = storage.pl = c_addr;
  ([c_op], storage);
};

It makes me wonder if this will lead to endpoints that are like "order" and "pickup", ie a restaurant.