Book Image

Solidity Programming Essentials

Book Image

Solidity Programming Essentials

Overview of this book

Solidity is a contract-oriented language whose syntax is highly influenced by JavaScript, and is designed to compile code for the Ethereum Virtual Machine. Solidity Programming Essentials will be your guide to understanding Solidity programming to build smart contracts for Ethereum and blockchain from ground-up. We begin with a brief run-through of blockchain, Ethereum, and their most important concepts or components. You will learn how to install all the necessary tools to write, test, and debug Solidity contracts on Ethereum. Then, you will explore the layout of a Solidity source file and work with the different data types. The next set of recipes will help you work with operators, control structures, and data structures while building your smart contracts. We take you through function calls, return types, function modifers, and recipes in object-oriented programming with Solidity. Learn all you can on event logging and exception handling, as well as testing and debugging smart contracts. By the end of this book, you will be able to write, deploy, and test smart contracts in Ethereum. This book will bring forth the essence of writing contracts using Solidity and also help you develop Solidity skills in no time.
Table of Contents (17 chapters)
Title Page
Copyright and Credits
Packt Upsell
Contributors
Preface
Index

The for loop


One of the most famous and most used loops is the for loop, and we can use it in Solidity. The general structure of a for loop is as follows:

for (initialize loop counter; check and test the counter; increase the value of counter;) {
 Execute multiple instructions here
  }

for is a keyword in Solidity and it informs the compiler that it contains information about looping a set of instructions. It is very similar to the while loop; however it is more succinct and readable since all information can be viewed in a single line.

The following code example shows the same solution: looping through a mapping. However, it uses the for loop instead of the while loop. The i variable is initialized, incremented by 1 in every iterator, and checked to see whether it is less than the value of counter. The loop will stop as soon as the condition becomes false; that is, the value of i is equal to or greater than counter: