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NEW QUESTION # 16
Refer to the following code:
<html lang="en">
<body>
<div onclick = "console.log('Outer message') ;">
<button id ="myButton">CLick me<button>
</div>
</body>
<script>
function displayMessage(ev) {
ev.stopPropagation();
console.log('Inner message.');
}
const elem = document.getElementById('myButton');
elem.addEventListener('click' , displayMessage);
</script>
</html>
What will the console show when the button is clicked?
- A. Outer message
Inner message - B. Inner message
- C. Outer message
- D. Inner message
Outer message
Answer: B
NEW QUESTION # 17
A developer has an ErrorHandler module that contains multiple functions.
What kind of export should be leveraged so that multiple functions can be used?
- A. all
- B. multi
- C. default
- D. named
Answer: D
NEW QUESTION # 18
Which code statement correctly retrieves and returns an object from localStorage?
- A. const retrieveFromLocalStorage = (storageKey) =>{
return JSON.parse(window.localStorage.getItem(storageKey));
} - B. const retrieveFromLocalStorage = (storageKey) =>{
return window.localStorage.getItem(storageKey);
} - C. const retrieveFromLocalStorage = () =>{
return JSON.stringify(window.localStorage.getItem(storageKey));
} - D. const retrieveFromLocalStorage = (storageKey) =>{
return window.localStorage[storageKey];
}
Answer: A
NEW QUESTION # 19
Refer to the code below:
Async funct on functionUnderTest(isOK) {
If (isOK) return 'OK' ;
Throw new Error('not OK');
)
Which assertion accuretely tests the above code?
- A. Console.assert (await functionUnderTest(true), 'OK')
- B. Console.assert (await functionUnderTest(true), ' not OK ')
- C. Console.assert (await functionUnderTest(true), ' OK ')
- D. Console.assert (await functionUnderTest(true), ' not OK ')
Answer: A
NEW QUESTION # 20
bar, awesome is a popular JavaScript module. the versions publish to npm are:
Teams at Universal Containers use this module in a number of projects. A particular project has the package, json definition below.
A developer runs this command: npm install.
Which version of bar .awesome is installed?
- A. 1.3.1
- B. The command fails, because version 130 is not found
- C. 1.4.0
- D. 1.3.5
Answer: D
NEW QUESTION # 21
developer is trying to convince management that their team will benefit from using Node.js for a backend server that they are going to create. The server will be a web server that handles API requests from a website that the team has already built using HTML, CSS, and JavaScript.
Which three benefits of Node.js can the developer use to persuade their manager?
Choose 3 answers:
- A. Performs a static analysis on code before execution to look for runtime errors.
- B. Uses non-blocking functionality for performant request handling .
- C. Executes server-side JavaScript code to avoid learning a new language.
- D. Installs with its own package manager to install and manage third-party libraries.
- E. Ensures stability with one major release every few years.
Answer: A,B,D
NEW QUESTION # 22
developer creates a new web server that uses Node.js. It imports a server library that
uses events and callbacks for handling server functionality.
The server library is imported with require and is made available to the code by a
variable named server. The developer wants to log any issues that the server has while booting
up.
Given the code and the information the developer has, which code logs an error at boost
with an event?
- A. Server.error ((server) => {
console.log('ERROR', error);
}); - B. Server.catch ((server) => {
console.log('ERROR', error);
}); - C. Try{
server.start();
} catch(error) { - D. Server.on ('error', (error) => {
console.log('ERROR', error);
});
Answer: D
Explanation:
console.log('ERROR', error);
}
NEW QUESTION # 23
Refer the following code
what is the value of array after code executes?
- A. [ 1, 2, 3, 5 ]
Answer: A
NEW QUESTION # 24
What are two unique features of functions defined with a fat arrow as compared to normal function definition?
Choose 2 answers
- A. If the function has a single expression in the function body, the expression will be evaluated and implicit returned.
- B. The function generated its own this making it useful for separating the function's scope from its enclosing scope.
- C. The function receives an argument that is always in scope, called parentThis, which is the enclosing lexical scope.
- D. The function uses the this from the enclosing scope.
Answer: A,B
NEW QUESTION # 25
A developer publishes a new version of a package with new feature that do not break backward compatibility. The previous version number was 1.1.3.
Following semantic versioning format, what should the new package version number be?
- A. 1.2.0
- B. 2.0.0
- C. 1.1.4
- D. 1.2.3
Answer: A
NEW QUESTION # 26
Refer to the code snippet:
A developer writes this code to return a message to a user attempting to register a new username. If the username is available, a variable named msg is declared and assigned a value on line 03.
What is the return of msg when getivelibilityMessage ('' bewUserName') is executed and getAvailability (''newUserName'') returns false?
- A. ''newUsername''
- B. ''msg is not defined''
- C. ''Username available''
- D. undefined
Answer: D
NEW QUESTION # 27
Universal Containers recently its new landing page to host crowd-function campaign. The page uses an external library to display some third-party ads. Once the page is fully loaded, It creates more than 50 new HTML items placed randomly inside the DOM, like the one in the code below.
All the elements included the same ad-library-item class. They are hidden by default, and they are randomly displayed while the user navigation through the page.
Tired of all the ads, what can the developer do to temporarily and quickly remove them?
- A. Use the DOM inspector to remove all the elements containing the call ad-library -item.
- B. Use the DOM inspector to prevent the load event to be fired.
- C. Use the browser console to execute a script that prevents the load event to be fired.
- D. Use the browser console to execute a script that removes all the elements containing the class ad-library-item.
Answer: D
NEW QUESTION # 28
Which two code snippets show working examples of a recursive function?
Choose 2 answers
A)
B)
C)
D)
- A. Option D
- B. Option A
- C. Option C
- D. Option B
Answer: A,C
NEW QUESTION # 29
Refer to the following code:
What is the output of line 11?
- A. ['foo'', ''bar'']
- B. [1, 2]
- C. [''foo:1'', ''bar:2'']
- D. [''bar'' , ''foo'']
Answer: A
NEW QUESTION # 30
A developer writes the code below to return a message to a user attempting to register a new username. If the username is available, a variable named nag is declared and assigned a value on line 03.
What is the value of msg when getAvailableabilityMessage ("newUserName") is executed and get Availability ("newUserName") returns true?
- A. "User-name available"
- B. "msg is not defined"
- C. "newUserName"
- D. undefined
Answer: A
NEW QUESTION # 31
At Universal Containers, every team has its own way of copying JavaScript objects. The
code
Snippet shows an implementation from one team:
Function Person() {
this.firstName = "John";
this.lastName = 'Doe';
This.name =() => (
console.log('Hello $(this.firstName) $(this.firstName)');
)}
Const john = new Person ();
Const dan = JSON.parse(JSON.stringify(john));
dan.firstName ='Dan';
dan.name();
What is the Output of the code execution?
- A. TypeError: Assignment to constant variable.
- B. Hello Dan Doe
- C. TypeError: dan.name is not a function
- D. Hello John DOe
Answer: C
NEW QUESTION # 32
developer wants to use a module named universalContainersLib and them call functions from it.
How should a developer import every function from the module and then call the fuctions foo and bar ?
- A. import all from '/path/universalContaineraLib.js';
universalContainersLib.foo();
universalContainersLib.bar(); - B. import (foo, bar) from '/path/universalContainersLib.js';
foo();
bar(); - C. import * ad lib from '/path/universalContainersLib.js';
lib.foo();
lib.bar(); - D. import * from '/path/universalContaineraLib.js';
universalContainersLib.foo();
universalContainersLib.bar();
Answer: C
NEW QUESTION # 33
A developer receives a comment from the Tech lead that the code below gives an error.
Which line edit should be made to make this code run?
- A. 03 if (year == 2019) (
- B. 02 const year = 2020;
- C. 01 let monthname = 'July ';
- D. 02 let year = 2019 ;
Answer: B
NEW QUESTION # 34
Considering type coercion, What does the following expression evaluate to?
True + '13 ' + NaN
- A. 113NaN
- B. 0
- C. 'true13'
- D. 'true13NaN'
Answer: A
NEW QUESTION # 35
A developer creates a new web server that uses Node.js. It imports a server library that uses events and callbacks for handling server functionality.
The server library is imported with require and is made available to the code by a variable named server. The developer wants to log any issues that the server has while booting up.
Given the code and the information the developer has, which code logs an error at boot time with an event?
A)
B)
C)
D)
- A. Option A
- B. Option C
- C. Option B
- D. Option D
Answer: B
NEW QUESTION # 36
Refer to the code below:
let productSKU = '8675309,;
A developer has a requirement to generate SKU numbers that are always 10 characters log, starting with 'sku', and padded with zeros.
Which statement assigned the value skuooooooooo86675309?
- A. productSKU = productSKU. PadEnd (16, '0' padstart (19, 'sku') ;
- B. productSKU = productSKU. Padstart (16, '0' padstart (19, 'sku') ;
- C. productSKU = productSKU. Padstart (19, '0' padstart ('sku') ;
- D. productSKU = productSKU. PadEnd (16, '0' padstart ('sku') ;
Answer: B
NEW QUESTION # 37
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