ISP

The ISP advocates for designing smaller, more specific interfaces rather than broad, general-purpose ones. This principle states that a class should not be forced to implement interfaces it does not use. In the context of Python, this implies that a class shouldn’t be forced to inherit and implement methods that are irrelevant to its purpose.

The ISP suggests that when designing software, one should avoid creating large, monolithic interfaces. Instead, the focus should be on creating smaller, more focused interfaces. This allows classes to only inherit or implement what they need, ensuring that each class only contains relevant and necessary methods.

Following this principle helps us build software with modularity, code readability and maintainability qualities, reduced side effects, and software that benefits from easier refactoring and testing, among other things.

An example of design following the ISP

Let’s consider an AllInOnePrinter class that implements...