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Omar
Omar

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Function Arguments Object in JS and how to use it

Assuming we all know what arguments are in JS functions

Function.arguments

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.

Example:

function exampleFunction(a, b, c) {
   console.log(arguments) // Arguments {0: 1, 1: 2}
  if (arguments.length !== 3) {
    throw new Error(`Invalid amount of arguments. Must be 3 and was ${arguments.length}`);
  }
}

exampleFunction(1,2) // Error: Invalid amount of arguments. Must be 3 and was 2
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