how to use the chain function from the underscore library in javascript

The chain function from the Underscore library in JavaScript allows you to chain multiple functions together to create a single, more concise function. The chain function returns a wrapped object that provides a way to chain multiple Underscore functions.

Here's an example of how to use the chain function:

index.tsx
const data = [1, 2, 3, 4, 5];

const result = _.chain(data)
  .map(num => num * 2)
  .filter(num => num % 3 === 0)
  .value();

console.log(result); // [ 6, 12 ]
162 chars
9 lines

In the code above, we start by passing our array of data to the _.chain() function. We then chain two functions, map() and filter(), to create a new array that contains only the elements that are multiples of 3. Finally, we call the value() function to return the result of the chained functions.

By chaining multiple functions together like this, we can easily create more complex, efficient code while keeping it readable and understandable.