A library to standardize the traits of producing and consuming.
The core purpose of this library is to define the traits of items that interact with markets. A market stores goods in its stock. Producers add goods to the stock while consumers remove goods from the stock.
One important characteristic of producers and consumers is that they are not modified by their respective action (producing or consuming). In other words, the signature of the action function starts with fn action(&self, not fn action(&mut self.