如何在不等待的情况下获得第一个请求的值 3？答案

【问题标题】：How to get the value 3 on the first request without await?如何在不等待的情况下获得第一个请求的值 3？
【发布时间】：2021-12-15 03:15:31
【问题描述】：

在这种情况下，如果有机会使用await，则没有理由创建问题，但不建议在合同中使用await：

注意：此功能旨在用于 debots，在通常的合同中使用它需要您自担风险。 https://github.com/tonlabs/TON-Solidity-Compiler/blob/master/API.md#synchronous-calls

Pong.sol

pragma ton-solidity ^0.51.0;

contract Pong {
    function get(uint b) external responsible returns (uint) {
        return b + 1;
    }
}

Ping.sol

pragma ton-solidity ^0.51.0;

interface IPong {
    function get(uint b) external responsible returns (uint);
}

contract Ping {
    uint public result;
    uint public tmp;

    function run(address pong, uint a) public view returns(uint) {
        update(pong, a);
        tvm.accept();
        return a + tmp;
    }

    function update(address pong, uint a) internal pure {
        IPong(pong).get{callback: Ping.onGet}(a);
    }

    function onGet(uint b) external {
        tvm.accept();
        tmp = b;
    }
}

运行.bash

#!/usr/bin/env bash

set -o errexit

tondev se reset

rm -fr *.abi.json *.tvc

# Deploy Pong Contract
tondev sol compile Pong.sol
tondev contract deploy Pong --value 1000000000
pongAddress=$(tondev contract info Pong | grep Address | cut -d':' -f3 | cut -d' ' -f1)
echo "$pongAddress"

# Deploy Ping Contract
tondev sol compile Ping.sol
tondev contract deploy Ping --value 1000000000
pingAddress=$(tondev contract info Ping | grep Address | cut -d':' -f3 | cut -d' ' -f1)
echo "$pingAddress"

# Run
tondev contract run Ping run --input "pong:$pongAddress,a:1" | grep value0
# value0:0x0000000000000000000000000000000000000000000000000000000000000001
tondev contract run Ping run --input "pong:$pongAddress,a:1" | grep value0
# value0:0x0000000000000000000000000000000000000000000000000000000000000003

问题的目的是了解如何在第一个请求中获得值 3（如果可能）。如果没有，那么更广泛地解释如何在异步区块链的条件下开发合约。

【问题讨论】：

标签： solidity everscale

【解决方案1】：

您可以更简单地以异步方式执行此操作（无需回调和等待）。

我更改了你的合约代码：

pragma ton-solidity ^0.51.0;

interface IPing {
    function onGet(uint b) external;
}

contract Pong {
    function get(uint b) external {       
        IPing(msg.sender).onGet(b + 1);        
    }
}

pragma ton-solidity ^0.51.0;

interface IPong {
    function get(uint b) external;
}

contract Ping {
    uint public tmp;

    function run(address pong, uint a) public  { 
        IPong(pong).get(a);
        tvm.accept();
        tmp = a + tmp;        
    }

    function onGet(uint b) external {
        tvm.accept();
        tmp = b + tmp;
    }
}

现在调用稍作改动的this Run.bash

#!/usr/bin/env bash

set -o errexit

tondev se reset
tondev network default se
rm -fr *.abi.json *.tvc

# Deploy Pong Contract
tondev sol compile Pong.sol
tondev contract deploy Pong --value 1000000000
pongAddress=$(tondev contract info Pong | grep Address | cut -d':' -f3 | cut -d' ' -f1)
echo "$pongAddress"

# Deploy Ping Contract
tondev sol compile Ping.sol
tondev contract deploy Ping --value 1000000000
pingAddress=$(tondev contract info Ping | grep Address | cut -d':' -f3 | cut -d' ' -f1)
echo "$pingAddress"

# Run
tondev contract run Ping run --input "pong:$pongAddress,a:1" &> /dev/null
tondev contract run-local Ping tmp | grep tmp
# tmp:0x0000000000000000000000000000000000000000000000000000000000000003

tondev contract run Ping run --input "pong:$pongAddress,a:1" &> /dev/null
tondev contract run-local Ping tmp | grep tmp
# tmp:0x0000000000000000000000000000000000000000000000000000000000000006

我的一点哲学，为什么它更好：合同必须在没有等待的情况下生效。所以回调和等待，这是不好的。回调在 debots 中非常有用，它可以在那里发生，因为 debots 在你的设备上运行。但这是另一个故事……

【讨论】：