How to Use Helper Functions?
Tags: javascript, webdev, beginners, programming
Published: 2024-06-01 15:10:09

In Javascript programming, the idea of helper functions is a fundamental principle that helps to improve code maintainability, readability, and efficiency. These functions are usually designed to perform specific tasks regularly required across different parts of an application. By making these tasks into separate, well-defined functions, software developers can avoid writing the same code multiple times, simplifying complex operations, and making the codebase look concise, clean, and easy to read and understand by other developers. This blog will cover more about the helper function, such as its characteristics, importance, benefits, some examples, and ways to organize more effectively and efficiently within more extensive applications.

##What are Helper Functions?##

Helper functions are small, reusable functions that carry out specific calculations or tasks. These functions encourage the DRY (Don’t Repeat Yourself) principle so that code is not unnecessarily duplicated across the application. This technique will help save effort and time, minimize the risk of bugs, and make it easy to change one piece of the code logic in one place.

##What are the Characteristics of Helper Functions?##

1. **Reusability** Helper functions are designed to be reusable so they can be reused in different parts of an application and other projects.
2. **Having No Side Effects:** Helper functions should not cause any side effects in the application or project. Their output should only depend on its input, which makes it easier to debug and predictable.
3. **Having a Single Responsibility:** Each helper function should only be responsible for one piece of functionality or operation. This makes functions more reusable and more accessible to debug.

##What are the Benefits of Helper Function?##

1. **Improve Readability:** Well-defined name helper functions can clarify the intentions behind a code block and make parts of the code more understandable and readable.
2. **Decrease Code Repetition:** The helper function can consolidate similar tasks and decrease code repetition. This can make the codebase more feasible and decrease the risk of bugs and errors.
3. **Make Testing Easier:** Since helper functions are designed to execute one task, they are much easier to test.
4. **Easy to Maintain:** Dedicating one task or functionality to a helper function simplifies changing, updating, and maintaining an application. If a specific functionality is needed, a change must be made only once in the code.

##Some Examples of Helper Functions##

Let’s see some examples where helper functions can be helpful:


###Calculation: Addition, Subtract, Multiply, & Divide###

```
const addition = (a, b) => {
 return a + b
}
```
```
const subtract = (a, b) => {
 return a - b
}
```
```
const multiply = (a, b) => {
 return a * b
}
```
```
const divide = (a, b) => {
 return a / b
}
```
All four functions above pass two numbers as arguments and return the result based on the operation: addition, subtraction, multiplication, or division. These functions can be useful and reused in making calculations like the total price of each item in the shopping cart.

###Capitalizing the First letter of a String###

```
const capitalizeFirstLetter = (string) => {
 return string.charAt(0).toUpperCase() + string.slice(1).toLowerCase();
}
```

The function will take in an input a string and separate it by uppercasing the first letter, lowering the rest of the letters, and combining them. This function is useful for ensuring that user input is always and consistently formatted.

###Capitalizing the First Letters of the Words in a Sentence###

```
const upperCaseFirstLetterInSentence = (string) => {
  return string.toLowerCase().split(' ').map(word => word.charAt(0).toUpperCase() + word.slice(1)).join(' ');
 }
```

The function will take input as a string, a sentence in this case, and return a new string in which the first letter of the words in the sentence is uppercase. This function would be very useful for formatting text for display purposes.

###Checking if a Number is Even###

```
const isEven = (number) => {
 return number % 2 === 0;
}
```

The function checks if a number is even or not. It takes a number, divides it by two, and checks if the remainder is equal to zero. The function is helpful because it’s reusable, so you don’t have to write the same code many times when checking if a number is even or not.


###Converting Fahrenheit to Celsius###

```
const fahrenheitToCelsius = (fahrenheit) => {
 return (fahrenheit - 32) * 5 / 9;
}
```

The function is simply a temperature conversion, converting Fahrenheit to Celsius. It is useful when making calculations in weather and science applications.

###How to Organize Helper Functions?###

There will be a time when you will use many help functions on big applications. So, organizing them will be essential to maintain a clean and concise codebase. A helpful tip is to group the helper functions into modules based on their functionality, such as numberUtils.js, stringUtils.js, or dateUtils.js, and import these modules when you need to use them or use their functionality. Another helpful tip is creating documentation explaining what each helper function does, the parameters, and return values. The last tip is to develop a suite of unit tests to ensure the helper functions are working as intended.

##Conclusion##

In conclusion, the helper function in Javascript is a powerful tool for developers who aim to promote and encourage code readability, reuse, and maintainability. Changing common tasks into reusable functions can make your code more manageable and straightforward to test, maintain, and read.

The takeaway from this blog is your understanding of the significance of helper functions. Thanks for reading the blog!