关于汽油退款的澄清以及智能合约中 “要求” 和 “还原” 之间的比较

Question

嘿大家，

我正在努力加深对智能合约开发中某些条件的理解，我有一个关于特定场景的问题.

假设智能合约中有一个 “要求” 条件必须得到满足. 如果此条件失效，合同需要恢复所有更改，并退还交易中使用的任何汽油. 我的问题是，考虑到在计算过程中总是消耗汽油，汽油退款流程是如何运作的？

此外，我听说过 “还原” 条件，但如果能澄清一下它与智能合约开发中的 “要求” 有何不同，我将不胜感激.

Sergey Ilin · Answer

There are 3 functions for validation in Solidity: require, revert, and assert. Require Used at the beginning of a function Validates against illegal input Verifies state conditions prior to execution Refunds leftover gas Example: require(msg.sender == owner, Only. owner can execute this action); Revert Identical to require Useful for more complex logic flow gates (i.e., complicated if-then blocks) Refunds leftover gas Example: revert(Something funky has occured); Assert Used at the end of a function Validates something that is impossible Critical for static code analysis tools Does not refund leftover gas Example: assert(num >= 0); Note that require and revert refund only the remaining gas. Any gas used before that statement will be consumed. Both these functions use the same opcode REVERT under the hood. assert is different because it does not refund any gas and uses all of the gas available for the transaction. It is expected to be used less frequently and should be used for checking conditions that are abnormal and not expected to happen.

关于汽油退款的澄清以及智能合约中 “要求” 和 “还原” 之间的比较

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