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

The filter function in the Underscore library allows you to filter an array of elements based on a provided condition. Here's an example of how to use it:

index.tsx
// Load the Underscore library
const _ = require('underscore');

// Sample array of numbers
const myArray = [1, 2, 3, 4, 5];

// Filter the array to only include even numbers
const filteredArray = _.filter(myArray, function(num) {
  return num % 2 === 0;
});
console.log(filteredArray); // Output: [2, 4]

// You can also use an arrow function for the condition
const anotherFilteredArray = _.filter(myArray, (num) => num > 3);
console.log(anotherFilteredArray); // Output: [4, 5]
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In this example, we first load the Underscore library using require(). Then, we create an array of numbers called myArray.

To filter this array, we call the _.filter() function and pass in the array as the first argument. The second argument is a function that defines the condition for filtering. In this case, we only want the even numbers to be included in the new array, so we use the modulo operator % to check if num is divisible by 2.

The filtered array is returned and stored in a new variable called filteredArray. We then log this array to the console, which should output [2, 4].

You can use any condition you want inside the filtering function, and you can also use arrow functions to make the code more concise.