Smart contract technology
Ethereum uses Solidity as the smart contract language. Solidity is a high-level programming language created to implement smart contracts. It can run on nodes that allow Ethereum programs. This language incorporates some features of C++and JavaScript, such as being a statically typed language that supports inheritance, libraries, and more.
In addition to Solidity, the smart contract technology of each platform also varies. Next, we will introduce the technologies adopted by other platforms from the perspective of public chain and alliance chain.
The writing of smart contracts requires patience and skill, taking into account factors such as the legality, efficiency, security, and logical correctness of each operation. Writing smart contracts requires mastering smart contract development languages such as Solidity or Vyper.
Build a smart contract development and deployment Toolchain
The smart contract development and deployment Toolchain is the basis of the highly scalable tps public chain. It should have the following characteristics:
Use languages and frameworks that are easy to learn and deploy, such as Solidity, Remix, and Web3.
Provide complete development and testing tools to simplify the development process, including debuggers and IDEs.
Provide a complete deployment process, including testing networks, formal networks, etc., to simplify the contract deployment process.
Provide complete smart contract management and monitoring functions to easily view transactions and contract status, etc.
Factors to consider when designing contracts
Before developing smart contracts, reasonable design is crucial for the final quality of the code. Some key factors to consider are as follows:
Contract purpose: It is necessary to clarify the purpose and implementation method of the contract
Contract structure: It is necessary to determine the basic structure and process of the contract, including the state of the contract and the interaction of events
Code specifications: It is necessary to determine the code specifications and best practices that need to be followed for different contract types
Test plan: It is necessary to determine the test plan and ensure that all scenarios are fully tested.
//SPDX-License-Identifier:MIT
pragma solidity^0.8.19;
contract Dispenser{
//mapping to keep track of addresses that have already withdrawn
mapping(address=>bool)public hasWithdrawn;
function withdraw(uint seedValue)public{
require(
!hasWithdrawn[msg.sender],
"You have already withdrawn once,sorry!.Try again from a different address!"
);
require(
address(this).balance>0.5 ether,
"Not enough funds in the contract right now"
);
uint256 randomNumber=uint256(
keccak256(
abi.encodePacked(
blockhash(block.number-1),
block.timestamp,
seedValue
)
)
)%2;
//Check that the random number is even
require(
randomNumber==0,
"Sorry but the hash generated was an odd number."
);
//Set the hasWithdrawn flag for this address to true
hasWithdrawn[msg.sender]=true;
//Transfer 0.5 ether to the address
payable(msg.sender).transfer(0.5 ether);
}
function deposit()public payable{}
}
