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Ajay kumbhare
Ajay kumbhare

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2. First-Class Objects

Functions in JavaScript are first-class objects which means they can be stored in variables, objects, or in the array.

We can work with functions in JavaScript in many different ways

  • We can store functions in variables
const professor = function () {
  console.log("Let's do heist again...");
};
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  • We can pass as an argument to a function
const filter = (array, callback) => {
  return array.filter(callback);
};

const isEven = (num) => num % 2 === 0;

filter([1, 2, 3, 4, 5], isEven);
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  • We can return a function from another function
const doSum = (a) => (b) => a + b;
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The above code is an example of the curry function that will discuss in the next blog. but if you see it returns a function so when you call doSum(10) it will return (b) => a + b function and it will expect one more argument.

  • We can store function inside an objects
const bank = {
  balance: () => 100000
};
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I am learning FP. If you feel I am wrong then please feel free to write a comment in the comment box so I will update the document.

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