The Solidity Programmer's Handbook

The Solidity Programmer's Handbook

By : Tony Hontzeas

Includes a section on Cryptocurrency Valuation

Copyright

Copyright © 2018 by Antonis Tony Hontzeas

All rights reserved.

This publication is designed to provide accurate and authoritative information in regard to the subject matter covered. It is sold with the understanding that the author is not engaged in rendering professional services. If legal, accounting, medical, psychological, or any other expert assistance is required, the services of a competent professional person should be sought. The author makes no representations or warranties including without limitation warranties of fitness  for a particular purpose.

The advice and strategies contained herein may not be suitable for every situation. The author shall not be liable for damages arising herefrom.

Library of Congress Cataloging-in-Publication Data:

Hontzeas, Antonis

The Solidity Programmer’s Handbook : Includes a special section on Cryptocurrency Validation

Includes resource references.

1. Solidity (Programming Language)     I. Hontzeas, Antonis  II. Title

ISBN #: 978-1-387-89551-9

Foreword

Dedicated to Chrysippus, Epictetus and Marcus Aurelius

We are at a dawn of a new age, a digital age. In the next 20 years we will see more changes taking place, than humanity has experienced in the last 300 years[1]. Self driving vehicles, biometric identification, preventive health through advanced predictive models, deep learning and machine intelligence and eventually a world wide seamless decentralized virtual computing platform.

About 2000 years ago Plato presented in The Republic the dangers of consolidating power and information to a single individual or an oligarchy, unless these individuals were ethically perfect. In Plato’s world the dilemma referred to as Who will watch the Watchers would only be solvable by a Philosopher King; historically the only individual to come close to this was Roman Emperor Marcus Aurelius.

In his celebrated book Voltaire’s Bastards John Raulston Saul reiterates Plato’s concern and further goes on to question the hierarchical rational organizational superstructures that the west has relied on for its administrative prowess. These superstructures aside from being slow and inefficient have also led to information concentration (amongst other things) and have led to accidents such as the 2008 crisis confirming Marx’s stipulation that Capitalism is its own worst enemy.

The market economy will survive only through transaction fluidity and healthy credible risk minimum transactions. Continued crises such as the 2008 world crisis breed anxiety and anxiety breeds insecurity which in itself breeds unrest, and unrest as Nicholas II of Russia had the misfortune to discover, brings about a series of unfortunate events.

Blockchain systems are peer to peer ledgers that automate in a risk free manner wealth transfer and eliminate the need for custodians, clearing houses, and any other types of bureaucracy that is intended to instill trust in a transaction. The blockchain’s inherent architecture provides a seamless peer to peer transparent to all distributed ledger system which stems from the fact that holdings and transactions are traceable, irrefutable, incorruptible and transparently open to viewing. Any type of digital asset whether digital currency, contracts such as trust funds and rental leases, birth certificates and so forth, can be coded as a smart contract and uploaded on a blockchain and remain there for all time –or as is necessary- thus allowing traceability, generation after generation.

Where other technologies bring local layered societal efficiencies, the blockchain as a concept implies an institutional change to the way we work and think about organizations, society, commerce and the general realization of value; gone are hierarchies and organizational superstructures in favor of organizational flat efficient computer intercommunication. Where other technologies may be considered optional, implementation of blockchain-like concepts are a must if commerce is to survive and flourish!

This book attempts to bring to light the important features of the blockchain and Ethereum and to introduce the reader to the Ethereum smart contact programming language known as Solidity.

The philosophy of this book is to introduce the reader to small snippets of Solidity code to enable quick understanding and to also permit the programmer to mix and match the code in various permutations; by learning simple parts, one can then build a complex whole whose sum of parts adds more value than the parts themselves.

We hope you enjoy this book, and we promise that the time invested will be well worth it.

Happy Trekking!

Tony Hontzeas

September 11th, 2018

linkedin Antonis Hontzeas

[1] Attributed to futurist Gerd Leonhard

The Big Picture

A blockchain is a growing list of records called blocks, which are linked using cryptography. Cryptography outlines techniques for secure communication in the presence of third parties and since its conception every blockchain, beginning with block 0 known as the Genesis node, is resistant to any change in the block data. The blockchain represents an open distributed ledger within a peer to peer network that can record transactions between two parties efficiently and in a verifiable and permanent way.   Once recorded, the data in any given block cannot be altered retroactively without alteration of all subsequent blocks, which requires consensus of the network majority. As such, blockchains are distributed computing systems which are considered generally secure and with a high degree of Byzantine fault tolerance.

Blockchains can be public, private, or a consortium or federated blockchain.

Public blockchains allow universal accessibility where anyone can participate in the process that determines which blocks get added to the chain and what the current shape and size of the blockchain is.  Examples of public blockchains include BitCoin, Ethereum, Litecoin, etc.

In a private Blockchain, write permissions are kept centralized to one organization. Read permissions may be public or restricted to any degree. Example applications of private blockchains include database management, auditing, etc. which are internal to a single company, and so public readability may be undesirable. 

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