If you have some familiarity with the software development, you must have possibly heard about the DRY principle of programming. This article introduces and describes this code development principle.
What is DRY programming?
DRY stands for “Do not Repeat Yourself.” It is a commonly used principle in software development, and as the name indicates, this principle aims to eliminate repetition within a software system. DRY aims to give a representation that is unique and unambiguous to the logic or data used in a code. This representation needs to be simple and authoritative as well. It is done with the help of normalization techniques to exclude redundant codes or data.
The principle was first proposed in a book named The Pragmatic Programmer, written by Dave Thomas and Andy Hunt.
It will be easier to understand the DRY system in contrast to the wet system.
DRY Programming vs. Wet Programming
While DRY means “Do not Repeat Yourself,” WET stands for “Write Every Time.” It is another commonly used coding principle widely used in multi-tier software projects. For example, the “comment” string is normally repeated in the HTML tag as well as in the database DDL.
Benefits of DRY Programming
Let’s see some of the major benefits of using DRY principles in coding.
- Easy to Maintain. If the program for any single logic is repeated throughout the software, it will be extremely difficult to fix any issues that may arise in this code. You will have to repeat the correction in every place where the same code is used, and you may easily miss out on one or two instances that need fixing. However, in programming DRY, this problem is totally avoided. In DRY, the code exists at a single place, and you can apply the fixes throughout by correcting that single instance only.
- Easy to Read and Understand. One of the main advantages of DRY code is that it is easy to read and understand.
- One of the fundamental ideas behind DRY is to merge repeating codes into a single one. This method makes a code that is written only once reusable, which drastically brings down the time required for developing programs.
- Cost Reduction. The most important reason why DRY coding is preferred is its cost reduction benefits. The smaller the amount of code, the fewer employee resources a firm needs to deploy to develop it, and the lower the cost of coding. The whole process speeds up, which also results in additional cost reduction and the company’s competitive advantage.
- Easy Testing. As the codes do not repeat in DRY programming, testing is much easier, as well. It is true both at unit-level testing and integration-level testing.
- Improved Customer Satisfaction. With shorter lead times, reduced cost, and lesser bugs and errors, customers are bound to be more satisfied with DRY programs.
Things to Remember while using DRY
- Sometimes developers tend to overdo the DRY principle, and in this effort, they make the code highly complicated and less readable, which needs to be avoided.
- DRYing may not be suitable in all instances. For example, there can be two different codes, which may look similar but have subtle differences. Thus, the code needs careful evaluation to decide whether it may be merged.
- The application of the DRY principle should not be restricted to the code. It also applies to database management, code testing, etc.
As one can see, the DRY programming principle is an important and increasingly used software coding practice. Hopefully, this discussion reveals its benefits and speaks in favor of its use for simplified, faster software development.