Layered Design - Functional Programming
Layered Design in Software: Simplifying Code Complexity
Layered design in software is a technique where software is organized into different layers. This approach allows each layer to function without needing detailed knowledge of the other layers. It's like building a cake layer by layer, where each layer has its own specific role.
The Direct Implementation Pattern
When we create functions or use language features, they often operate at different levels of abstraction. For example, using array indexes and loops is considered a lower level of abstraction.
If a single function mixes different levels of abstraction, it can make the code hard to read. It's like trying to read a book where every other paragraph switches between basic and advanced topics.
A function is said to be directly implemented if it operates consistently at the same level of abstraction. It's like staying on the same floor of a building rather than jumping between floors.
But why does mixing abstraction levels make code hard to read? Imagine each level of abstraction as a different box. If elements in a function belong to different boxes (or levels), it's harder to understand the function's overall purpose.
In the direct implementation pattern, it's ideal if all connections (like arrows in a diagram) are of the same length, indicating a uniform level of abstraction. If they're not, it's a sign that the function might not be directly implemented. A good solution is to introduce intermediate functions to bridge these gaps.