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

To use the all function from the Underscore library in JavaScript, you first need to include the library in your project. You can either download and include the library file manually or use a package manager like npm to install it.

Once you have included the library, you can use the all function to check if all elements of an array pass a certain condition. Here's an example:

index.tsx
const _ = require('underscore');

const numbers = [2, 4, 6, 8];

const areAllEven = _.all(numbers, function(x) {
  return x % 2 === 0;
});

console.log(areAllEven); // true
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In this example, we're using the all function to check if all elements of the numbers array are even. The function takes two arguments: the array to iterate over and the condition to check. In this case, the condition is a function that checks if a number is even by checking if its remainder when divided by 2 is 0.

The all function returns a boolean value that is true if all elements of the array pass the condition, and false otherwise. In this example, the areAllEven variable will be set to true since all elements of the numbers array are even.