Do Drawing Flowcharts Help Before Starting to Code?

When approaching the task of coding, decisions about whether to start with detailed flowcharts can often be quite divisive. Some argue that flowcharts are essential for capturing the design and logic of a project, while others like to jump into pseudocode or a functional specification directly. In this article, we explore the arguments for and against using flowcharts, as well as some alternative approaches that might be more effective.

Flowcharts: A Mixed Bag

Flowcharts have long been the go-to tool for visualizing the logic of a program, with their block diagram representing the flow of control and decision-making processes. However, for some, they become quickly cluttered and lose their effectiveness as tools for immortalizing design details. According to many seasoned developers, including those with decades of experience, flowcharts may not be the best choice for every project.

One common criticism of flowcharts is that they can drift from the final implementation. As the project progresses and the code evolves, the flowchart might become outdated, leading to a disconnect between the two. Moreover, flowcharts are not adept at representing complex concepts such as iteration, recursion, or asynchronous processes. A well-worn piece of advice is that if a flowchart becomes too complicated to draw, it's often a sign that the design is not yet clear or well-conceptualized.

Alternatives to Flowcharts

Many proficient coders find that they get better results by starting with a functional specification and then moving on to pseudocode for the unclear parts. This approach allows for more direct and adaptable communication of design ideas. Pseudocode is a form of high-level description of the code that is written in a way that resembles a natural language, providing a clear and concise way to lay out the logic of the program.

State Diagrams: An Alternative to Flowcharts

For projects that involve complex logic or asynchronous operations, state diagrams can be a more effective tool than traditional flowcharts. State diagrams represent the different states a system can be in and the transitions between those states based on certain events. They are particularly useful for modeling systems with complex behavior, different states of a program, or asynchronous processes with a variable event order.

While flowcharts can occasionally be adapted to represent these scenarios, they often fall short when it comes to clarity and precision. In such cases, state diagrams offer a more intuitive and easier-to-understand representation of the system's behavior. By mastering state diagrams, developers can effectively document and communicate the logical flow of their software more efficiently.

Practical Application and Industry Trends

Over the years, the use of flowcharts in industry has seen a gradual decline. Even in the early days of commercial computing, with mainframe systems like the IBM360 and DEC machines, programmers rarely drew detailed flowcharts unless they were doing so post-hoc for training purposes. The pendulum has swung towards more direct approaches like pseudocode and functional specifications.

As the field of software development has evolved, the use of pseudocode has become more prevalent. It is now more common for developers to work in a language like C, which is ubiquitous in professional settings, and less frequently in BASIC. However, the utility of flowcharts can still be found in certain contexts, such as early days of assembly language programming or in specific situations where visual diagrams can help clarify logic.

For younger professionals like the author's son, who has a background in more modern languages like C, the use of clear and concise pseudocode has become the norm. By choosing to communicate design and logic in a way that is natural and familiar to the team, developers can ensure that everyone is on the same page from the outset.

Conclusion

While flowcharts can be a helpful tool in certain scenarios, they are not a one-size-fits-all solution for every coding project. For many, starting with a clear functional specification and moving to pseudocode is a more effective approach. State diagrams can also be a valuable alternative when dealing with complex logic or asynchronous processing.

Ultimately, whether or not to use flowcharts depends on the specific context and the needs of the project at hand. It's important to choose the right tool for the job and to communicate effectively with your team. By doing so, you can build software that is both well-designed and effectively implemented.