Solidity

Going threw https://cryptozombies.io to learn Solidity

Contracts

Solidity code is encapsulated in contracts which are the building blocks of Ethreum applications. All variables and functions belong to a contract

contract HelloWorld {
 
}

All code should include the version pragma which tells the version of the Solidiy compiler our code uses.

pragma solidity >=0.5.0 <0.6.0;
 
contract HelloWorld {
 
}

Are variables that are permanently stored to contract storage. Which means they are written to the Ethereum Blockchain

contract Example { 
	// This will be stored permanently in the blockchain 
	uint myUnsignedInteger = 100; 
}

Work similar to most programming languages +, -, /, *

if you want to do say 5^2 you would do 5 ** 2

struct Person { 
	uint age; 
	string name; 
}

Both fixed and dynamic

unit[5] fixedArray;
string[] dynamicArray;
Person[] people //Array of structs

you can make an array public which will automatically give an array a getter method

Person[] public people;

function eatHamburgers(string memory _name, uint _amount) public { 

}

in the above method we are using a reference type variable (string) when we do this we want to state where the data location is memory

There are three data location types. memory, storage, and calldata

It is also best practice to add an _ to the beginning of function parameter variables

by default functions are public

When making a private function it is convention to give the function the _ naming

function _eatHamburgers(string memory _name, uint _amount) private { 
 
}

There are 2 method modifiers view - Can only view data but not modify it pure - No accessing data in the app

Example of a view function:

string greeting = 'Hello';
 
function sayHello() public view returns (string memory) {
	return greeting;
}

Example of a pure function:

function _multiply(uint a, uint b) private pure returns (uint) { 
	return a * b; 
}