Gain insights into software design patterns in C, explore their implementation, discover underlying principles, and learn to build a vocabulary for better communication and coding practices.

c.tar.gz

main+customer.c

main+customer.c-copy

watches

customers

observer

Reactor

Reactor-copy

observer-copy

Software design patterns are a valuable tool in any software developer's skill set. However, most design patterns are described in the context of an object-oriented programming language such as C++ or Java. The C language is sadly absent in the pattern literature. This course is here to change that by demonstrating that it is possible to use patterns in C programs and how it adds benefits to C programmers. You will learn why design patterns are more of a communication tool than technical solutions, and how patterns let you build and share a common vocabulary that simplifies communication.

The course presents a number of patterns and explains how to implement them in C. Each pattern is introduced via the problem it solves and the domains where the pattern can be used. We also discuss the underlying design principles as well as the trade-offs when applying the pattern. Finally, the course covers a set of coding idioms that will guide you when applying design patterns in C.

Software Design Patterns in C

Although mainly seen in the context of object-oriented literature, the open-closed principle defines
properties attractive in the context of C too. The principle is summarized as **"Software entities (classes,
modules, functions, etc.) should be open for extension, but closed for modification."** ([Martin](https://www.educative.io/courses/software-design-patterns-c/conclusion))

**According to the open-closed principle:** 
* Extending the behavior of an ideal module is achieved by
adding code instead of changing the existing source. 
* Following this principle minimizes the risk
of introducing bugs in existing, tested code and typically raises the quality of the design by introducing
loose coupling. 
* Unfortunately, it is virtually impossible to design a module so that it is closed
against all kinds of changes. 
* Even trying to design software in such a way would overcomplicate the
design far beyond suitability. 
* Identifying which modules to close and what changes to close them against requires experience and a good understanding of the problem domain.

In this lesson, we will explain the implementation of  the Strategy pattern in the C language.


Implementing the Strategy  Pattern

In this lesson, we will explain the implementation of  the Strategy pattern in the C language.

Introduction to Pattern in C

The First-Class ADT Pattern

The State Pattern

The Strategy Pattern

The Observer Pattern

The Reactor Pattern

Idiomatic Expressions

Conclusion

Implementing the Strategy Pattern

The open-closed principle