how to use the differenceinweeks function from the date-fns library in typescript

To use the differenceInWeeks function from the date-fns library in TypeScript, you can follow the below steps:

1. Install the date-fns library using npm by running the following command:

   index.ts
   npm install date-fns
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2. Import the differenceInWeeks function from the date-fns library in your TypeScript file as shown below:

   index.ts
   import { differenceInWeeks } from 'date-fns';
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3. Call the differenceInWeeks function by passing the two date objects as arguments as shown below:

   index.ts
   const startDate = new Date('2021-01-01');
   const endDate = new Date('2021-06-01');
   const weeksDifference = differenceInWeeks(endDate, startDate);
   console.log(weeksDifference); // Output: 21
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   In the above example, the differenceInWeeks function is called by passing two date objects as arguments, and the returned value is stored in the weeksDifference variable.

   Note that the order of the dates passed as arguments is important. The resulting value will be positive if the endDate is greater than the startDate and negative if the startDate is greater than the endDate.

   Also, make sure that the dates are valid JavaScript Date objects. If the dates are invalid, the function will throw a TypeError.