Blockchain Quick Start Guide

State machine

State machine is a behavior design pattern.  It allows a contract to alter its behavior when it's internal state changes. A smart contract function call typically moves a contract state from one stage to the next stage. The basic operation of a state machine has two parts:

• It traverses through a sequence of states, where the next state is determined by the present state, and input conditions.
• It provides sequences of outputs based upon state transitions.

To illustrate this, let's develop a simple state machine. We will use washing dishes as an example. The process typically is scrub, rinse, dry, scrub, rinse, dry. We defined state machine stages as an enumerated type.  As this is an extensive use case, only the state machine ...