I want to remove only the last element. Why does it remove every element except the last one? Answer You need to omit the assignment. If you like just to delete the last one, you could take a negative index with Array#splice. This works for any other index from the end.
Tag: arrays
Behavior of “Greater than” (and another inequality comparison operators) on arrays
I couldn’t find any description or any mention about how >, <, <= and >= operators behave while comparing two arrays in javascript. The only trivial thing I could think of is that the two arrays are compared by both elements for each relative indexes, but after testing it – I didn̵…
Why does the copy of an array using the spread operator when run through map modify the original array?
Why does the copy of an array using the spread operator when run through map modify the original array? What should i do here to not mutate the original array? Answer The spread operator creates shallow copy of the array. In other words, you create a new array with references to the same objects. So when you …
A very big sum – Hacker Rank
I am trying to solve “A very big sum” challenge on Hacker Rank: https://www.hackerrank.com/challenges/a-very-big-sum/problem In there I have to sum all the numbers in the array given so I came up with two solutions: First solution Second Solution But none of them work and I don´t know why, I am th…
refactoring assistance with reducing some array data objects in JavaScript
I need to reduce data in profiles array in a way such that the final object groups the data in profile obj based on the favorite movie and the users that liked/favorited the movie. I want something like: from the following data objects: I need some ideas in refactoring the following code for it to go back to …
How do you add multiple objects to an array? (JavaScript)
I’m not sure if I phrased the question right. I’m fairly new to JavaScript, and I’d like to add multiple objects (?) to an array. If I have this array: How would I add, say as to the same array? Answer Items can be added to an array with the push method. Every array has this method build it,…
How to display the contents of an array as a list?
I’d like to output the contents of an array as a list: value value value However, it’s currently outputting the array like this: value,value,value What can I change to display the array contents as a vertical list? For context, this is displaying an array that updates by adding/removing items base…
How to create a class that holds collection of other class in JavaScript
I want to create a class called SchoolCatalog that will hold a collection of schools, e.g. Create an instance of SchoolCatalog for primary, middle, and high schools. (This is one of the problems from Code Academy Introduction To JavaScript). But, they have no proper guide on how to make a Catalog to hold all …
Javscript function running slow
I’m collecting a lot of data from an API with an async function that cycles through a lot of data with a loop, I’m making about 100 requests and it takes around 8 seconds. Are there any methods I can try to use, to speed up my script? Answer Instead of for loops with await inside, which runs in se…
Filtering an array of objects by user defined properties based on user inputted search term
That title might not make a lot of sense but please bear with me and I’ll try to explain what I’m after. I’m creating an Angular filter component that I can plug and play into various portions of my app. However, the question itself is more of a JavaScript question than an Angular one. What …