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

To use the isDate function from the date-fns library in Typescript, you can follow these steps:

1. First, install the date-fns library using npm:

   index.ts
   npm install date-fns
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2. Import the isDate function from the date-fns module in your Typescript file:

   index.ts
   import { isDate } from 'date-fns';
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3. Use the isDate function in your Typescript code by passing a value you want to test as an argument. The function returns a boolean value indicating whether the input is a date or not:

   index.ts
   const date = new Date('2022-01-30');
   const isInputDate = isDate(date);
   console.log(isInputDate); // Output: true
   
   const string = '2022-01-30';
   const isInputStringDate = isDate(string);
   console.log(isInputStringDate); // Output: false
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4. Optional: If you want to add type annotations, you can declare the input variable with a type of Date | string:

   index.ts
   const input: Date | string = '2022-01-30';
   const isInputValidDate = isDate(input);
   console.log(isInputValidDate); // Output: false
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Here are some examples of how to use the isDate function with different input variables:

index.ts
// Example 1: Using a valid date object
const validDate = new Date('2022-01-30');
const isValidDate = isDate(validDate); // true
console.log(isValidDate);

// Example 2: Using an invalid date object
const invalidDate = new Date('invalid date');
const isInvalidDate = isDate(invalidDate); // false
console.log(isInvalidDate);

// Example 3: Using a string that represents a valid date
const validDateString = '2022-01-30';
const isValidDateString = isDate(validDateString); // false
console.log(isValidDateString);

// Example 4: Using a string that represents an invalid date
const invalidDateString = 'invalid date';
const isInvalidDateString = isDate(invalidDateString); // false
console.log(isInvalidDateString);

// Example 5: Using a number that represents a timestamp
const timestamp = Date.now();
const isTimestampDate = isDate(timestamp); // false
console.log(isTimestampDate);
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