Modular Programming

One of the more effective programming practices involves partitioning large, complex programming challenges into smaller and more manageable sub-tasks and reusable functions. A similar approach should be taken when using a programming language like Cicode to complete a task. Reducing the task to smaller tasks (or functions) has the following advantages:

• Reduced Complexity - Once the function is created and tested, the detailed operation about how it works need not be revisited. Users need only focus on the results produced by the function.
• Avoids Duplicate Code - Creating a generic function instead of copying similar code reduces the total amount of code in the system. It also means the function can be reused by separate code areas. This makes the code more maintainable because it is smaller in size, and only one instance needs to be modified.
• Hides Information - Information can be in the form of operations, data, or resources. Access to information can be controlled when functions are written that provide a limited set of actions to be performed on the information. For example, if a user wishes to log a message to a database, he or she should only send the message to a function, say LogDBaseMessage("hello world"), and the function should control the database resource. The function then becomes the single interface to the database resource. Resources that have multiple interfaces to them are harder to control. This is because in a multitasking environment, the user cannot control or even know in advance the order of code execution, and hence a resource may be modified at the same time by different tasks. Information hiding can also smooth out any wrinkles in standard functions, minimizing possible misuse of resources such as semaphores, queues, devices, and files. Functions that do this are often called `wrapper' functions as they add a protective shell to existing functions.
• Improves Performance - Optimizing code that resides in one place immediately increases the performance of code that calls this function. Scattered code will require multiple areas to be modified should any optimization be necessary.
• Isolates Complex Code - Code that requires complex operations such communications protocols, complex algorithms, boolean logic, or complex data manipulation is susceptible to errors. Placing this code in a separate function reduces the possibility of this code corrupting or halting other code.
• Improves Readability - A small function with meaningful parameter names assists readability as it is a step towards self-documenting code and reduces the need to scan multiple pages of code to establish what the operation is meant to achieve.

Modular programming has a few rules that define how functions should be structured - Cohesion - and how they are related to other functions - Coupling.

See Also

Defensive Programming

Using Cicode Programming Standards