{ "data": { "question": { "questionId": "2758", "questionFrontendId": "2618", "boundTopicId": null, "title": "Check if Object Instance of Class", "titleSlug": "check-if-object-instance-of-class", "content": "

Write a function that checks if a given object is an instance of a given class or superclass.

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There are no constraints on the data types that can be passed to the function.

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Example 1:

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\nInput: func = () => checkIfInstance(new Date(), Date)\nOutput: true\nExplanation: The object returned by the Date constructor is, by definition, an instance of Date.\n
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Example 2:

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\nInput: func = () => { class Animal {}; class Dog extends Animal {}; return checkIfInstance(new Dog(), Animal); }\nOutput: true\nExplanation:\nclass Animal {};\nclass Dog extends Animal {};\ncheckIfInstance(new Dog(), Animal); // true\n\nDog is a subclass of Animal. Therefore, a Dog object is an instance of both Dog and Animal.
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Example 3:

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\nInput: func = () => checkIfInstance(Date, Date)\nOutput: false\nExplanation: A date constructor cannot logically be an instance of itself.\n
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Example 4:

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\nInput: func = () => checkIfInstance(5, Number)\nOutput: true\nExplanation: 5 is a Number. Note that the "instanceof" keyword would return false.\n
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Node.js 16.13.2.

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Your code is run with --harmony flag, enabling new ES6 features.

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lodash.js library is included by default.

\\r\\n\\r\\n

For Priority Queue / Queue data structures, you may use 5.3.0 version of datastructures-js/priority-queue and 4.2.1 version of datastructures-js/queue.

\"], \"typescript\": [\"Typescript\", \"

TypeScript 4.5.4, Node.js 16.13.2.

\\r\\n\\r\\n

Your code is run with --harmony flag, enabling new ES2020 features.

\\r\\n\\r\\n

lodash.js library is included by default.

\"]}", "libraryUrl": null, "adminUrl": null, "challengeQuestion": null, "__typename": "QuestionNode" } } }