Solidity 文档薄荷并发送 function

Question

In the documentation solidity has this coin example, I read the documentation but I couldn't understand what is the difference and purpose of both? What mint and send functions are doing? The send function makes sense but mint function is confusing. What is the meaning of "Sends an amount of newly created coins to an address, can only be called by the contract creator"

Answer 1

When the coin contract is deployed, there is nothing to use as long as you create something. The process of creating coins is referred to as minting.

Sends an amount of newly created coins to an address Minting is usually perceived to be sending coins somewhere from nowhere. This may sound confusing but think of it this way:

If you want a regular transfer: address(Alice) sends to address(Bob)

If you have a method to do: address(Nothing) to address(Contract Creator), now you can create coins.

can only be called by the contract creator

This makes sense since minting creates value out of thin air, and this contract wants to allow no one but the creator.

Answer 2

If you look at the mint function, it has this require statement:

 // msg.sender is the account that calls the function
 require(msg.sender==minter)

so only "minter" can call this. "Minter account" will be creating the token and distributing the token to other accounts or selling tokens. So contract owner creator and financial admin are separated. You set the minter when you deploy the contract:

    // you declare the state variable first
    address public _minter;

    // you assign a value during the construction of the contract

    constructor(address minter_){
        _minter=minter_;        
     }

In object-oriented programming, constructor is called when you create an instance of the class. In solidity we create an instance of contract when we deploy the contract. When we deploy the contract we have to pass this parameter. If you deploy on remix, you would have this:

you have to enter the minter address into the box.

• send function is defined as public, so anyone can call it. In above example, it is just used to send some coin to receiver account.