# Class Inheritance

Flowchem employs a high level of class inheritance for devices through the use of
[class and inheritance](https://pythonbasics.org/inheritance/). This approach represents individual device components
based on their functions, simplifying the process of creating new equipment from scratch. Also, Inheritance allows the
system to improve code reusability and ease maintenance. To illustrate, consider the table and figure below:

| Class of the System | Description              | Main Function            |
|---------------------|--------------------------|--------------------------|
| Azura Compact Pump  | Specific Device Component| Implement & run Commands |
| HPLC Pump           | Specific Component       | Define Specific Commands |
| Pump                | Base Component           | Define Base Commands     |
| Flowchem Component  | Base Class               | Base Constructor         |

In the example addressed in the table we have the following hierarchy:

![](inherit.JPG)

1. **Flowchem Component**: The base class for all devices.
2. **Pump**: Inherits from flowchem Component, includes basic pump commands.
3. **HPLC Pump**: Inherits from Pump, includes specific commands for HPLC pumps.
4. **Azura Compact Pump**: Inherits from HPLC Pump, includes configuration for a specific device model.

## How Inheritance Works in flowchem

When creating a class to represent a device, such as the ***Azura Compact Pump***, it inherits attributes and methods
from the ***HPLC Pump*** class. The ***HPLC Pump*** class provides standard commands specific to its category of pumps.
This class, in turn, inherits from a more generic ***Pump*** class, which includes basic commands common to all pumps,
such as `is-pumping` and `infuse`. Furthermore, the ***Pump*** class inherits from a base class that contains attributes
and methods applicable to all devices.

## Benefits of This Inheritance

1. **Ease of Device Switching**: Users can quickly switch between devices that share the same functions (i.e., inherit
commands from the same parent class). This is possible even if the devices come from different suppliers or use different communication protocols.
2. **Minimal Code Changes**: Switching devices requires no changes to the existing code structure related to the
platform's automation. The only change needed is in the configuration file, which is easily editable.
3. **Code Reusability**: By using inheritance, flowchem avoids code duplication. Methods and attributes defined in a
parent class are automatically available in all child classes, promoting the principle of "Don't Repeat Yourself" (DRY).

Citations:
[1] https://pythonbasics.org/inheritance/