Arguments object

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The arguments object is a local variable available within all non-arrow functions. You can refer to a function's arguments inside that function by using its arguments object. It has entries for each argument the function was called with, with the first entry's index at 0.

function func1(a, b, c) {
  console.log(arguments[0]); // expected output: 1

  console.log(arguments[1]); // expected output: 2

  console.log(arguments[2]); // expected output: 3

func1(1, 2, 3);