Summary GitHub - lydiahallie/javascript-questions: A long list of (advanced) JavaScript questions, and their explanations github.com
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The GitHub repository "lydiahallie/javascript-questions" is a well-liked resource with a vast collection of advanced JavaScript questions, explanations, and a significant number of stars and forks.
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Slide Presentation (11 slides)
Key Points
- The GitHub repository "lydiahallie/javascript-questions" contains a long list of advanced JavaScript questions and their explanations.
- The repository has 55.4k stars and 7.9k forks.
- The document is a compilation of JavaScript questions and their answers, covering various topics such as output determination, return values, constructors, and pure functions.
- The document is regularly updated with new questions.
- JavaScript methods are available on the prototype, allowing them to be accessed even if not directly on the object.
- The unary plus operator can result in NaN and 63 in a particular code snippet.
- The Promise.race method resolves/rejects the first promise that resolves/rejects.
- Properties can be deleted from objects using the delete keyword.
Summaries
25 word summary
The popular GitHub repository "lydiahallie/javascript-questions" contains a comprehensive list of advanced JavaScript questions and explanations, covering various topics. It has 55.4k stars and 7.9k forks.
31 word summary
The GitHub repository "lydiahallie/javascript-questions" contains a comprehensive list of advanced JavaScript questions and their explanations. The repository has gained popularity with 55.4k stars and 7.9k forks. The questions cover various topics
937 word summary
GitHub repository "lydiahallie/javascript-questions" contains a long list of advanced JavaScript questions and their explanations. The repository has 55.4k stars and 7.9k forks. The questions cover various topics such as output determination
The excerpt contains a series of JavaScript questions and their corresponding answers. The questions cover various topics such as output, return values, constructors, and pure functions. The answers are labeled with letters ranging from A to D.
The document is a list of JavaScript questions and their corresponding answers. The questions range from asking about the output of certain code snippets to inquiring about the value of specific variables. The answers are provided for each question. The document also includes questions about the
The document is a compilation of JavaScript questions and their answers. The questions range from basic to advanced and are designed to test one's knowledge of JavaScript. The answers are provided in collapsed sections below each question. The document is regularly updated with new questions.
The first loop in the code uses the var keyword, making the variable global. The second loop uses the let keyword, making the variable block-scoped. The output of a particular code snippet is NaN and 63. The unary plus operator tries to
JavaScript methods are available on the prototype, allowing them to be accessed even if not directly on the object. The function "sum" returns the value "2" as a string. The output is "12" because JavaScript converts the number into a string
"Third" is logged because the WebAPI pushes the callback function to a queue and the event loop pushes it onto the stack if the stack is empty. The event.target when clicking the button is C, the button itself. When clicking the paragraph,
When multiple promises are passed to the Promise.race method, it resolves/rejects the first promise that resolves/rejects. In this case, the secondPromise resolves first with the value of 'two', so 'two' is logged.
When
We can delete properties from objects using the delete keyword. When a property is deleted from the prototype, it is no longer available in the prototype chain. Trying to access a deleted property will result in a TypeError.
The Set object is a collection of
The value of num2 is 10 because the unary operator ++ increments the value of num1 after returning its value. The output of the code is 20, 40, 20, 40, as the multiply function is called multiple times
In the first excerpt, the code utilizes string concatenation to create an empty string. A generator function is used to "pause" execution with the yield keyword. String.raw ignores escape characters. An async function returns a pending promise until it is resolved.
The add function is a memoized function that caches the results to speed up execution. The function checks if the value is already in the cache, and if so, returns the cached value. Otherwise, it calculates the value and stores it in the cache
The setTimeout function uses the global object, so 'this' refers to the global object. The value of 'status' on the global object is an empty string, so logging 'this.status' would return an empty string.
The variable 'city
The first excerpt explains that the .push method in JavaScript returns the new length of an array, not the array itself. If you try to use the .push method on a numerical value, like newList in this case, a TypeError is thrown.
The
The getList function receives an array as its argument and uses destructuring to assign values. The getUser function receives an object and arrow functions require parentheses when returning an object. A TypeError is thrown when trying to invoke a string as a function. The value of
In JavaScript, we can get the value of a promise using either .then or the await keyword in an async function. The difference is that with .then, the code continues to run while the promise is being resolved, whereas with await, the execution
The first excerpt discusses the use of the splice method in JavaScript, which allows for modification of an array by deleting, replacing, or adding elements. It clarifies that map, filter, and slice return new arrays, find returns an element, and reduce
116. The changeAge function increases the age property of the person object by 1. The changeAgeAndName function does not affect the values of the properties on the person object. 117. The spread operator (...) spreads the elements of an iterable to
When accessing values within an arrow function, the JS engine goes up the scope chain to find the appropriate values. In one example, a generator function returns an async object with promises for each item in a range. The resolved values of the promises are then
Currently, counterTwo.count is 133. We invoke counterTwo.increment(), which sets count to 134. Then, we log the count on counterOne, which logs 133. The output is: Last line 1! Promise 2
With a Proxy object, custom behavior can be added to an object. The handler object contains two properties: set and get. Set is invoked when setting property values, and get is invoked when accessing property values. Adding a property to the object invokes set
In the first excerpt, a Flamingo class is defined and instantiated. The constructor of the Flamingo class logs "I'm pink." and then calls the constructor of the parent class, Bird, which logs "I'm a bird." The
The splice method is used to modify the original fruit array by removing elements. The unshift method is then used to add a value to the beginning of the array. The output is an array with three empty strings.
When accessing object properties using square