Implementing isRef in Vue.js

Vue.js provides a powerful reactivity system, and a core part of this system is the concept of "Refs." Refs are wrappers around values that allow Vue to track changes and update the UI accordingly. In many situations, you need to determine if a given value is a Vue Ref. This challenge asks you to implement a TypeScript function that replicates Vue's internal isRef check.

Problem Description

Your task is to create a TypeScript function named isRef that accepts a single argument and returns true if the argument is a Vue Ref, and false otherwise.

Key Requirements:

• The function must be written in TypeScript.
• It should correctly identify objects that are Vue Refs.
• It should not misidentify non-Ref values as Refs.

Expected Behavior:

• If an object has a special internal property that signifies it's a Vue Ref, isRef should return true.
• If an object does not have this property, or if the property is not indicative of a Ref, isRef should return false.

Edge Cases to Consider:

• null and undefined should not be considered Refs.
• Plain JavaScript objects and arrays should not be considered Refs.
• The function should be robust enough to handle various types of input, including primitive values.

Examples

Example 1:

// Assume this is a Vue Ref object (simplified for illustration)
const myRef = { __v_isRef: true, value: 10 };

// Input: myRef
// Output: true

Explanation: The myRef object has the __v_isRef: true property, which is the internal marker Vue uses to identify Refs. Therefore, isRef(myRef) should return true.

Example 2:

// Input: 10
// Output: false

Explanation: A primitive number is not a Vue Ref. Therefore, isRef(10) should return false.

Example 3:

// Assume this is a plain JavaScript object, not a Vue Ref
const plainObject = { name: 'Vue', version: 3 };

// Input: plainObject
// Output: false

Explanation: The plainObject does not possess the __v_isRef property. Therefore, isRef(plainObject) should return false.

Example 4:

// Input: null
// Output: false

Explanation: null is a primitive value and not a Vue Ref. Therefore, isRef(null) should return false.

Constraints

• The function must be named isRef.
• The function should accept any type of input.
• The solution should aim for efficiency, avoiding unnecessary computations.

Notes

Vue.js uses a specific internal property to mark its Ref objects. Your primary goal is to identify this marker. You do not need to recreate the entire Vue reactivity system, just the isRef checking logic. Consider how to safely access properties on potentially null or undefined inputs.