191–200 of 411 posts
Why did they create a flatMap method? What is wrong with .map(...).flat()? Can they improve the performance by combining it that much?
Why is flatMap = map().flat() and not flat().map()
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What would some common/helpful use cases be?
Functional transformation of objects. There are lots of HOFs working on arrays / iterators but none working on object. fromEntries allows easily converting from object to entries, manipulating the entries sequence and converting back to an object. The last step is pretty annoying without it. The entire thing is very common in Python, where Object.entries() is spelled `.items()` and `Object.fromEntries(…)` is spelled…
That array.flat() and array.flatMap() stuff is great to see. Always having to rely on lodash and friends to do that type of work. Exciting to see how JS is evolving.
I dig it too, but you could previously flatten an array with concat, and the spread operator. [].concat(...array) Lodash wasn't necessary.
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String#padStart already exists: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...
But we still have trimLeft() and trimRight() and in true JS tradition we need some more redundancy for symmetry's sake.
All major engines have also implemented corresponding trimLeft and trimRight functions - without any standard specification.
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That's not unique to JS. Some compilers took over a decade to implement C99 features. Most of us C coders were still defaulting to C89 for portability well into the late 00's. But now C99 is mainstream enough that you can (mostly) safely target it. If you never release new standards you'll never be able to use them. I realize that in JS world 4 years is basically an eternity so it's hard to project that far but I'm s…
> It's popular to be sure but handwritten javascript is not that rare nowadays, is it? Long time front end developer here. In the last couple of years I can't recall seeing even a single project without a build pipeline (not that they don't exist, I just haven't encountered them at my day job, first or third party).
I ended up adding Parcel for easy Typescript support.
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Clojure too didn't change a lot. In these years of 'disruption' it feels odd. But it may just be that we forgot stability and maturity.
Existing Clojure APIs don't change, but Clojure adds a lot more than this each year. Look at spec, reducers, transducers &c
Honest question, not meant to be inflammatory. If we still need to target es5 4 years later, and transpilation is standard practice, why bother? Is the evolution of JS not directed in practice by the authors of Babel and Typescript? If no one can confidently ship this stuff for years after, what’s the incentive to even bother thinking about what is official vs a Babel supported proposal. I like the idea of idiomatic…
That's not unique to JS. Some compilers took over a decade to implement C99 features. Most of us C coders were still defaulting to C89 for portability well into the late 00's. But now C99 is mainstream enough that you can (mostly) safely target it. If you never release new standards you'll never be able to use them. I realize that in JS world 4 years is basically an eternity so it's hard to project that far but I'm s…
Whereas in JS-land, the support for upgrades is even more trailing because it's the end-users who need to upgrade, not just the individual/organization doing the packaging.
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> It's popular to be sure but handwritten javascript is not that rare nowadays, is it? Long time front end developer here. In the last couple of years I can't recall seeing even a single project without a build pipeline (not that they don't exist, I just haven't encountered them at my day job, first or third party).
I made this recently just because I wanted to prove to myself that it was possible to have a modern frontend application without all the overhead of build tooling and I have to say I'm pretty happy with it. You can use some of the most important things in browsers today like CSS variables, and ES module imports. https://gitlab.com/WA9ACE/frontend-starter