The Identity Function Challenge

The identity function is a fundamental concept in functional programming. It simply returns its input unchanged. This challenge asks you to implement this function in JavaScript, reinforcing your understanding of basic function definition and return values, which are crucial building blocks for more complex code.

Problem Description

You are tasked with creating a JavaScript function called identity. This function should accept a single argument and return that same argument without modification. The purpose of an identity function is to demonstrate a function that does nothing but pass its input through.

What needs to be achieved:

• Create a function named identity.
• The function must accept one argument.
• The function must return the same argument that was passed to it.

Key Requirements:

• The function must be named identity.
• It must accept a single parameter.
• It must return the parameter unchanged.

Expected Behavior:

When called with any input, the identity function should return that same input. The input can be of any data type (number, string, boolean, object, array, etc.).

Edge Cases to Consider:

• null and undefined inputs: The function should return null or undefined respectively.
• Empty inputs (e.g., an empty string or array): The function should return the empty input.
• Complex data structures (objects, arrays): The function should return the same object or array reference.

Examples

Example 1:

Input: 5
Output: 5
Explanation: The function receives the number 5 and returns it unchanged.

Example 2:

Input: "hello"
Output: "hello"
Explanation: The function receives the string "hello" and returns it unchanged.

Example 3:

Input: [1, 2, 3]
Output: [1, 2, 3]
Explanation: The function receives an array and returns the same array reference.

Example 4:

Input: null
Output: null
Explanation: The function receives null and returns null.

Constraints

• The function must be written in JavaScript.
• The function must be named identity.
• The function must accept exactly one argument.
• The function must return the argument without modification.
• The function should handle all valid JavaScript data types.

Notes

This is a very simple problem, but it's a good exercise in understanding function definition and return values. Consider how the function behaves with different data types. There's only one correct way to implement the core logic of the function. Focus on clarity and conciseness.