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

The every function from the Underscore library allows you to test whether every element in an array passes a particular condition. Here’s how you can use it:

First, you need to include the Underscore library in your project. You can do this by adding the following line of code to your HTML file:

<script src="underscore.js"></script>
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Next, you can use the every function to test whether every element in an array passes a particular condition. Here’s the basic syntax:

index.tsx
_.every(list, [predicate], [context])
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• list: This is the array you want to test.
• predicate: This is the function that tests each element in the array.
• context: This is the optional context that the predicate function will be called with.

The predicate function should return a boolean value that indicates whether the element passes the test. If every element in the array passes the test, the every function returns true. Otherwise, it returns false.

Here’s an example that uses the every function to test whether every element in an array is greater than 0:

index.tsx
var numbers = [1, 2, 3, 4, 5];
var result = _.every(numbers, function(num) {
  return num > 0;
});
console.log(result); // Output: true
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In this example, the _.every() function returns true because every element in the numbers array is greater than 0.

Note that you can also use the every function with an object instead of an array. In this case, the predicate function will be called with each value in the object.