JavaScript is a very flexible and easy-to-write language, but its flexibility can sometimes lead to unexpected bugs during large-scale development.
I passed a number to a function that expected a string'' or I accessed a non-existent property from an API response’’ - everyone has experienced these errors at least once.
In this article, we will use a problem-and-solution approach to understand why TypeScript is essential for modern web application development.
Challenge: Fear of not knowing the bug until it is executed
The biggest weakness of applications written in pure JavaScript is that errors in the code are only discovered at runtime. You won’t notice the error unless you actually click a button in the browser or go to a specific screen. This results in an extremely risky development process where bugs are only discovered through omissions in testing by the QA team or defect reports from users.
Solution: Powerful armor called “type”
By introducing TypeScript, this issue will be dramatically improved.
TypeScript brings the concept of “static typing” to JavaScript. Rules (types) can be established for variables, function arguments, and return values, such as This is a string'' or This is an object with a specific structure.''
This allows the editor to warn you that the value you are passing here is of a different type while you are writing code or building it. This means that many bugs can be prevented before they occur.
Challenge: Introduction learning cost and amount of description
However, there are many workplaces that hesitate to introduce it because it is troublesome to write type definitions and the learning cost is high.
Admittedly, at first you may be confused by unfamiliar concepts such as interface, type definitions, and generics. The amount of code written will also increase temporarily.
Solution: Overwhelming editor complementation and medium- to long-term productivity
However, that initial investment can be quickly recovered. TypeScript is a great compatibility with modern editors such as VS Code. Having a type defined allows the editor to perfectly infer what properties an object has and provides powerful auto-completion.
Once you experience the experience of being able to suggest the next entry you should enter just by pressing a dot, without having to go out of your way to look at documents or specifications, you will never go back. Even in team development, functions written by other people can be safely called, resulting in reduced communication costs and improved development speed.
Instead of a summary
At first, you may feel like you are being forced to follow complicated rules. However, TypeScript’s type system does not bind developers; it is a “shield” that protects developers from the fear of bugs. If you want to create web applications that are robust and long-lasting, give TypeScript a try.