Member-only story
The Power of Template Design Pattern in JavaScript
Templates come in many forms
If you’ve used nodejs before, then you know that packages are at the heart of this platform. Every day and every second, there is either a new update or a new package published to the npm registry. The majority of these packages are reusable and extensible. The way they do this can be one of many ways, but there’s one common trait they all share: They can be seen as templates that are waiting for you to execute them.
This post will go over the template design pattern in JavaScript. We will go in-depth on this pattern’s approach and discuss one scenario where we should use it. We will also see a diagram of how the structure looks “outside the box.”
And finally, we will implement the pattern in code so you will be comfortable with templating in JavaScript by the end of this article.
How Does the Template Pattern Work?
When we are implementing this pattern, a useful way to approach this is to think about the start phase of something and the end phase.
Sometimes, when we write functions, the first thing we think about is how their parameters and how their variables will be initialized. Eventually, we decide how to end that function.
What happens in the middle depends on the implementation.
This is similar to how the flow of the template works.
In more official terms, it’s essentially a bare interface that is given to the consumer so they can implement one or more steps of the algorithm without changing the structure.
After they define those steps and follow the execution, the “end” phase is reached just like a basic function.
When Is the Template Pattern Needed?
It’s most needed in scenarios where two functions have important similarities in implementation or interface but share the same problem because they can’t reuse those similarities. This means that when there is an update to one of the function’s implementation, the other function needs to update its implementation as well. This is a bad practice and eventually becomes unmaintainable if not dealt with.
