Higher Order Functions: A JavaScript Strong Point

How does the concept of higher order functions relate to first class functions? What is a higher order function? In this tutorial we answer these questions and show an example of a higher order function using the sort method to alphabetically sort the elements in an array.
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[@RameenFallschirmjager]

I like your intonation and voice crescendo. In the way that you talk we learners understand the points and concepts better.

[@kc2838]

You teach very clearly and to the point. That's a skill not a lot of youtubers have. Subscribed and waiting for more javascript videos.

[@AllThingsJavaScript]

Thanks and welcome

[@AllThingsJavaScript]

I have almost 200 available, so you may want to look at whats out there: th-cam.com/channels/RQhZGXC0WK85YRXl7nGX0w.html?view_as=subscriber

[@AllThingsJavaScript]

Or allthingsjavascript.com/youtube.html

[@IcarianX]

I have no idea where the arguments "a" or "b" are. How does the program determine what variables are passed in as "a" and "b" and what are they?

[@AllThingsJavaScript]

By definition sort passes the first two arguments into a and b. It then continues to move through each element of the array.

[@saeedkhan4927]

I really love your teaching style. Just started Lambda school, and this is really helping me understand the content and material that is being taught. Thank you!

[@saeedkhan4927]

Just one question, I was following along with your code and I am getting a syntax error. Is this updated to ES6 or does this only apply to ES5 - or does it even matter?

[@AllThingsJavaScript]

Higher order functions have been a part of JavaScript from early on and is still an important aspect of it. So doesn't really matter was ECMAScript release. Post your code if you are still getting an error.

[@jasonwilliams_escapeimagery]

Was so pleased to find your channel some great topics and presentations thanks.

[@dsnow]

For reuse and less coupled code, you could define a function expression that performs the comparison that returns a.toLowerCase() - b.toLowerCase() and then pass that function into sort. Nice tutorial.

[@dembasiby]

Great, simple, and to the point. Thanks!

[@geoffblore]

Thanks for the help!

[@Corythehausbaus]

dude, so many people doing tutorials talk so fast, monotone, and sounds the same the entire time. Not you! Please continue to talk dynamically and really emphasise on the key words!!!!

[@omleen3187]

Much appreciated for the perfect explanation. Juat one question, please! Which sort algorithm used with javascript sort method? Thanks!

[@AllThingsJavaScript]

Good question. I'm not sure which one and it really probably depends on the JavaScript Engine implementation. So technically a browser could use a different algorithm than another one.

[@mj2758]

QuickSort and InsertionSort, for smaller arrays

[@bkleinman123]

How did you know that the sort function takes in another function that has the rules of returns left first if negative number and so on? Is that in a javadoc type thing online that I can look up?

[@AllThingsJavaScript]

I don't remember how I first learned it, but I think the MDN pages are great for this kind of thing: developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/sort

[@KevinMullarkey]

How would you write this as an 'arrow function'?

[@AllThingsJavaScript]

things.sort((a,b) => {
let x = a.toLowerCase(),
y = b.toLowerCase();
if (x < y) { return -1;}
if (y < x) { return 1;}
return 0;
});

[@KevinMullarkey]

I keep getting an error 'toLowerCase is not a function'

[@AllThingsJavaScript]

Post your code.

[@Shirokeh]

Thanks for the content. How is progress on the asynchronous course? Have seen it in the status of upcoming and projected release for September for so long!

[@AllThingsJavaScript]

Great Question! I need to go in an update that page. I haven't been able to start that one yet, but it is the next course once I finish up two smaller items I'm working on. I'm adding a section on functional programming to the advanced course and a course on regular expressions. When projects come along, they take priority. There has been a lot of that lately that has slowed me down on the courses.

[@RameenFallschirmjager]

Thank you sir for your great explanation. Your tutorials are so compelling that I decided to get your udemy courses too!

[@AllThingsJavaScript]

Thanks for the support!

[@sarathbabu7689]

Can able to create my own higher function like map, sort and etc

[@AllThingsJavaScript]

Yes, anyone can create a higher order function.

[@seenuvasanv]

Thanks, really useful..

[@luismuzquiz1400]

Steven Could you do a video or a UDEMY course on Vue.js for beginners??

[@AllThingsJavaScript]

That would probably be a course or maybe a series of TH-cam videos to get one started. But I will add it to the list.

[@shyarxelil1987]

why don't you use els if statment?

[@AllThingsJavaScript]

I do when needed. Are you referring to a specific example?

[@DopamineMVWM]

why is this guy talking so fucking slow; even on x2 speed its too slow!