how to use the differenceinyears function from date-fns in javascript

The differenceInYears function from the date-fns library is used to get the difference between two dates in years. Here's how to use it:

1. First, you need to install the date-fns library. You can do this using npm by running the following command in your terminal:

   index.tsx
   npm install date-fns
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2. Once you've installed the library, you can import the differenceInYears function in your javascript file like this:

   index.tsx
   const { differenceInYears } = require('date-fns');
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   Alternatively, you can use the ES6 import statement like this:

   index.tsx
   import { differenceInYears } from 'date-fns';
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3. Now you're ready to use the differenceInYears function. Here's the basic syntax:

   index.tsx
   const start = new Date(2010, 0, 1);
   const end = new Date(2020, 0, 1);
   
   const years = differenceInYears(end, start);
   
   console.log(years); // Output: 10
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   In this example, we create two date objects, start and end, and then pass them to the differenceInYears function. The function returns the number of years between the two dates, which we store in the years variable.

   The output of the console.log statement is 10, which is the number of years between 2010 and 2020.

   Note that the differenceInYears function rounds down to the nearest whole number of years. So if the difference between two dates is 11 months and 29 days, it will still return 0 years.