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feat(curriculum): create objects quiz (#56583)
Co-authored-by: Krzysztof G. <60067306+gikf@users.noreply.github.com> Co-authored-by: Naomi <accounts+github@nhcarrigan.com>
This commit is contained in:
Tunmise Ogunniyi
co-authored by
Krzysztof G.
Naomi
Krzysztof G.
Naomi
parent
fa7f31c50d
commit
f37cd31880
+130
-100
@@ -17,439 +17,469 @@ Answer all of the questions below correctly to pass the quiz.
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#### --text--
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Placeholder question
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Which of the following does not describe an object in Javascript?
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#### --distractors--
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Placeholder distractor 1
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A collection of key-value pairs
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---
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Placeholder distractor 2
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A container for properties and methods
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---
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Placeholder distractor 3
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One of Javascript's data types
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#### --answer--
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Placeholder answer
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One of Javascript's primitives
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### --question--
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#### --text--
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Placeholder question
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Which of the following object definitions is invalid?
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#### --distractors--
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Placeholder distractor 1
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`const obj = { key: "some-value" }`
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---
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Placeholder distractor 2
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`const obj = { "some-value": key }`
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---
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Placeholder distractor 3
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`const obj = { key: () => "some-value" }`
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#### --answer--
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Placeholder answer
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`const obj = { key(): "some-value" }`
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### --question--
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#### --text--
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Placeholder question
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Which of the following correctly accesses the value of the `key` property in the object below:
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```js
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const obj = { key: "some-value" }
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```
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#### --distractors--
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Placeholder distractor 1
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`obj -> key`
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---
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Placeholder distractor 2
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`obj#key`
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---
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Placeholder distractor 3
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`obj[key]`
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#### --answer--
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Placeholder answer
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`obj.key`
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### --question--
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#### --text--
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Placeholder question
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Which of the following correctly accesses the value of the `street` property in the object below?
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```js
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const person = {
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address: {
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street: "sample-street"
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}
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}
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```
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#### --distractors--
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Placeholder distractor 1
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`person -> address -> street`
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---
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Placeholder distractor 2
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`person#address#street`
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---
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Placeholder distractor 3
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`person[address.street]`
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#### --answer--
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Placeholder answer
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`person["address"]["street"]`
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### --question--
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#### --text--
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Placeholder question
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Which of the following property key can only be used with a bracket notation as opposed to dot notation?
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#### --distractors--
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Placeholder distractor 1
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A property key that is known and static
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---
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Placeholder distractor 2
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A property key nested in multiple levels of the object
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---
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Placeholder distractor 3
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A property key that might not exist in the object
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#### --answer--
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Placeholder answer
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A property key that is dynamic
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### --question--
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#### --text--
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Placeholder question
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Which of the following correctly accesses the value of `name` property via destructuring in the object below?
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```js
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const person = { name: "John" }
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```
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#### --distractors--
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Placeholder distractor 1
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`const name = person.name`
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---
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Placeholder distractor 2
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`const name = person["name"]`
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---
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Placeholder distractor 3
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`const { ...name } = person`
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#### --answer--
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Placeholder answer
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`const { name } = person`
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### --question--
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#### --text--
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Placeholder question
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Which of the following correctly accesses the value of `street` property via destructuring in the object below?
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```js
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const person = {
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address: {
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street: "sample-street"
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}
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}
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```
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#### --distractors--
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Placeholder distractor 1
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`const name = person.address.street`
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---
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Placeholder distractor 2
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`const name = person["address"]["street"]`
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---
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Placeholder distractor 3
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`const { address: street } = person`
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#### --answer--
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Placeholder answer
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`const { address: { street } } = person`
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### --question--
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#### --text--
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Placeholder question
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How do you assign a default value of `"defaultValue"` to a property key accessed via destructuring?
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#### --distractors--
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Placeholder distractor 1
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`const key = object.key && "defaultValue"`
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---
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Placeholder distractor 2
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`const key = object.key || "defaultValue"`
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---
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Placeholder distractor 3
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`const { key: "defaultValue" } = object `
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#### --answer--
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Placeholder answer
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`const { key = "defaultValue" } = object`
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### --question--
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#### --text--
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Placeholder question
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Which of the following objects does not inherit from `Object.prototype`?
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#### --distractors--
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Placeholder distractor 1
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`const obj = Object.create(undefined)`
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---
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Placeholder distractor 2
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`const obj = new Object(null)`
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---
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Placeholder distractor 3
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`const obj = { proto: undefined }`
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#### --answer--
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Placeholder answer
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`const obj = Object.create(null}`
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### --question--
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#### --text--
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Placeholder question
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Which of the following cannot be an object prototype?
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#### --distractors--
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Placeholder distractor 1
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`Math`
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---
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Placeholder distractor 2
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`Date`
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---
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Placeholder distractor 3
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`null`
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#### --answer--
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Placeholder answer
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`undefined`
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### --question--
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#### --text--
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Placeholder question
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Which of the following correctly creates an object with the prototype below:
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```js
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const samplePrototype = {
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doSomething: () => {}
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}
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```
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#### --distractors--
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Placeholder distractor 1
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`const obj = { proto: samplePrototype }`
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---
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Placeholder distractor 2
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`const obj = { prototype: samplePrototype }`
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---
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Placeholder distractor 3
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`const obj = new Object(samplePrototype)`
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#### --answer--
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Placeholder answer
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`const obj = Object.create(samplePrototype)`
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### --question--
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#### --text--
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Placeholder question
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Which of the following keywords is used to identify a getter in an Object?
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#### --distractors--
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Placeholder distractor 1
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`getter`
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---
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Placeholder distractor 2
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`get_`
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---
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Placeholder distractor 3
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`_get`
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#### --answer--
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Placeholder answer
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`get`
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### --question--
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#### --text--
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Placeholder question
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Which of the following keywords is used to identify a setter in an Object?
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#### --distractors--
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Placeholder distractor 1
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`setter`
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---
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Placeholder distractor 2
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`set_`
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---
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Placeholder distractor 3
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`_set`
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#### --answer--
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Placeholder answer
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`set`
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### --question--
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#### --text--
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Placeholder question
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Which of the following is true about object setters?
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#### --distractors--
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Placeholder distractor 1
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An object setter must be called with a parenthesis
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---
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Placeholder distractor 2
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An object setter must be defined with the same name as the property it sets
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---
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Placeholder distractor 3
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An object setter must be accompanied by a getter
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#### --answer--
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Placeholder answer
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An object setter must be defined with exactly one argument
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### --question--
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#### --text--
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Placeholder question
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Which of the following is the correct syntax for optional chaining?
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#### --distractors--
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Placeholder distractor 1
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`object.key`
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---
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Placeholder distractor 2
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`object.["key"]`
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---
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Placeholder distractor 3
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`object.?key`
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#### --answer--
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Placeholder answer
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`object?.key`
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### --question--
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#### --text--
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Placeholder question
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What is the difference between enumerable and non-enumerable properties in an object?
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#### --distractors--
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Placeholder distractor 1
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Enumerable properties are owned by the object while non-enumerable properties are not.
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---
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Placeholder distractor 2
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Enumerable properties are defined by the object while non-enumerable properties can only be inherited.
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---
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Placeholder distractor 3
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Enumerable properties can be accessed via dot notation while non-enumerable properties can only be accessed via bracket notation
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#### --answer--
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Placeholder answer
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Enumerable properties are properties whose internal enumerable flag is set to true while non-enumerable properties' internal enumerable flag is set to false
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### --question--
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#### --text--
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Placeholder question
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What is the difference between `Object.keys()` and `Object.getOwnPropertyNames()`?
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#### --distractors--
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Placeholder distractor 1
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`Object.keys()` returns all the properties prefixed with the word `key_` while `Object.getOwnPropertyNames()` returns all object properties regardless of prefix.
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---
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Placeholder distractor 2
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`Object.keys()` returns all properties inherited and owned by the object while `Object.getOwnPropertyNames()` only returns properties owned by the object.
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---
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Placeholder distractor 3
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`Object.keys()` and `Object.getOwnPropertyNames()` will always return the same list of properties.
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#### --answer--
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Placeholder answer
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`Object.keys()` returns only enumerable properties of an object while `Object.getOwnPropertyNames()` returns enumerable and non-enumerable properties except for those which use Symbol.
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### --question--
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#### --text--
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Placeholder question
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Which of the following is true for an object sealed with `Object.seal`?
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#### --distractors--
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Placeholder distractor 1
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Values of existing properties cannot be changed
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---
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Placeholder distractor 2
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Values of existing properties can be changed but doing this will unseal the object
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---
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Placeholder distractor 3
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New properties can be added but existing properties can not be removed
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#### --answer--
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Placeholder answer
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New properties cannot be added and existing properties cannot be removed
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### --question--
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#### --text--
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Placeholder question
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Which of the following is true for an object frozen with `Object.freeze`?
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#### --distractors--
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Placeholder distractor 1
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New properties can be added but existing properties can not be removed
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---
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Placeholder distractor 2
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New properties can be added but doing this will unfreeze the object
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---
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Placeholder distractor 3
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Values of existing properties can be changed but doing this will unfreeze the object
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#### --answer--
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Placeholder answer
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Values of existing properties cannot be changed
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### --question--
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#### --text--
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Placeholder question
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What is the right way to completely remove a property from an object?
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#### --distractors--
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Placeholder distractor 1
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`Object.delete(object, propertyKey)`
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---
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Placeholder distractor 2
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`remove object.propertyKey`
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---
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Placeholder distractor 3
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`object.propertyKey = undefined`
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#### --answer--
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Placeholder answer
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`delete object.propertyKey`
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Reference in New Issue
Block a user