Very good input. I have a single critique, though, and this is ONLY because you're prepping: with reduce. Me, as a hiring person, I question deeper when candidates don't provide the third init value.
I know it's arguably pointless, especially when implicit inits come into play, but that's how it is. And you'll come across others who think the same.
To reiterate, this is gold. But those little things... A lot of times, hiring people will grab onto them and dig deeper. (Probably not what you want for a smooth-as-butter interview lol)
I was on mobile last night and I've been busy today, so I honestly didn't expect to have a reply. ...but whaddaya know, I JUST NOW used a reduce lol.
The init value - technically - protects you from a TypeError if you encounter an empty array. init, if not provided, is implicitly taken from arr[0]. If !arr[0]... Muerte.
Here, I'm writing a cypress e2e test that finds all the card rows in the page and guarantees the contained cards are the same height. To do so, I sum the heights of all the cards, divide that by cards.length, and compare the final avg to cards[0]. (a variance inside will break the cards[0]===avg, I hope :D)
Not such a problem with Cypress, but it could be possible that there are no cards in the row.
Most uses of reduce aren't for summing, though. Its return - more often than not - is a complex object, rather than a simple value. In these cases:
arr[0] can't properly init the product, because product and items have very different structures.
providing an init that models the outcome helps self-document the code (other devs see in the call an idea of what to expect), and it save you a ton of checks internally.
it.only('cards within a row are equal-height',()=>{cy.get('[data-t="card-row"]').each(row=>{letheights=[]cy.wrap(row).find('div.card').each(card=>heights.push(Math.floor(card.innerHeight()))).then(()=>{letavgHeight=heights.reduce((prev,curr)=>prev+curr,0)/heights.lengthexpect(heights[0]).to.eq(avgHeight)})})})
Very good input. I have a single critique, though, and this is ONLY because you're prepping: with reduce. Me, as a hiring person, I question deeper when candidates don't provide the third init value.
I know it's arguably pointless, especially when implicit inits come into play, but that's how it is. And you'll come across others who think the same.
To reiterate, this is gold. But those little things... A lot of times, hiring people will grab onto them and dig deeper. (Probably not what you want for a smooth-as-butter interview lol)
Interesting, Iād love to learn more, could you expound with an example?
I was on mobile last night and I've been busy today, so I honestly didn't expect to have a reply. ...but whaddaya know, I JUST NOW used a reduce lol.
The init value - technically - protects you from a
TypeErrorif you encounter an empty array. init, if not provided, is implicitly taken fromarr[0]. If!arr[0]... Muerte.Here, I'm writing a cypress e2e test that finds all the card rows in the page and guarantees the contained cards are the same height. To do so, I sum the heights of all the cards, divide that by cards.length, and compare the final avg to
cards[0]. (a variance inside will break thecards[0]===avg, I hope :D)Not such a problem with Cypress, but it could be possible that there are no cards in the row.
Most uses of reduce aren't for summing, though. Its return - more often than not - is a complex object, rather than a simple value. In these cases:
arr[0]can't properly init the product, because product and items have very different structures.Very cool! Thanks for sharing this example.