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

The _.matches function from the Underscore library in JavaScript allows you to create a predicate function for filtering objects that match a specific set of key-value pairs. The function takes an object as an argument and returns a boolean value indicating whether the object matches the specified key-value pairs.

Here is an example of how to use _.matches to filter an array of objects based on a certain key-value pair:

index.tsx
const array = [{name: 'John', age: 25}, {name: 'Mary', age: 30}, {name: 'Bob', age: 25}];
const matcher = _.matches({age: 25});

const filteredArray = _.filter(array, matcher);
console.log(filteredArray); // [{name: 'John', age: 25}, {name: 'Bob', age: 25}]
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In this example, we create an array of objects representing people, and we want to filter this array to only include people who are 25 years old. We first create a matcher function using _.matches({age: 25}). This function will return true for any object that has an age key with a value of 25.

We then use the _.filter function from Underscore to apply this matcher function to each object in the original array, returning a new array with only the objects that match our criteria.

Note that _.matches is also capable of using regular expressions to match values, as shown in the following example:

index.tsx
const array = [{name: 'John', age: 25}, {name: 'Mary', age: 30}, {name: 'Bob', age: 25}];
const matcher = _.matches({name: /Jo.*/});

const filteredArray = _.filter(array, matcher);
console.log(filteredArray); // [{name: 'John', age: 25}]
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In this example, we filter the array to only include objects whose name key starts with "Jo". We achieve this by using a regular expression in the matcher object.