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Brian discusses filtering and equality comparison in reference to array methods.

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Transcript from the "Array Methods Q&A" Lesson

>> Brian Holt: Yeah.
>> Speaker 2: So, looking ahead, how long do you think it'll take before JavaScript just lets you say to uppercase? [LAUGH] Cuz that's what I wanna do [LAUGH]
>> Brian Holt: I mean, we could. This is gonna be way more gross, but you could totally do strings. Let's say aconst x = this is some thing.

So, I can say x.split.
>> Brian Holt: Split allows me to split this string into an array of characters, and then I can map s to s.toUpperCase()). Okay, now everything in here is uppercase, and then here I'm just going to join.
>> Brian Holt: Now this was absolutely pointless, but I enjoyed it [LAUGH]

>> Brian Holt: But again, this is kind of the fun parts of the more functional style of programing. You have these transformations that kind of take place over line by line.
>> Brian Holt: And we can even put something in here. There's one called filter.
>> Brian Holt: So filter takes an array, and whatever you return true and stays in the array, and whatever you return false on removes from the array.

So let's say we're super against having Is in our strings so we wanna filter out all the Is, so I could say this would take in some string and it returns that S is not equal to I.
>> Brian Holt: And now all of my Is are gone.
>> Brian Holt: So this looks weird right?

This is exclamation.= equals, but it's combining those together into that thing.
>> Brian Holt: Did I talk about not equals yesterday? I probably didn't, did I? Okay, worth talking about, [LAUGH]
>> Brian Holt: Let's talk about them.
>> Brian Holt: I think it's pretty, hopefully implicit.
>> Brian Holt: So we talked about equal equals right, and triple equals, so if triple equals two, then console.log these are equal.

>> Brian Holt: Right? We got there. This is just three equal signs next to each other, but now I wanted to ask, are they not equal to each other, so I'll do != equals, okay? So as two not equal to three, these are not equal.
>> Brian Holt: So, just replace one of the equal signs with an exclamation point and that'll ask the question, are these things not equal?

Make sense?