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

Function input and output


Functions would not be that interesting if they didn't accept parameters and return values. Functions are made generic with the use of parameters and return values. Parameters can help in changing function execution and providing different execution paths. Solidity allows you to accept multiple parameters within the same function; the only condition is that their identifiers should be uniquely named.

The following code snippets show the following multiple functions, each with different constructs for parameters and return values:

  1. The first function, singleIncomingParameter, accepts one parameter named _data of type int and returns a single return value that is identified using _output of type int. The function signature provides constructs to define both the incoming parameters and return values. The return keyword in the function signature helps define the return types from the function. In the following code snippet, the return keyword within the function code automatically...