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A comment on Show HN: I taught my little brother JS, and he made this videogame in a week. Parent comment

Re:Show HN: I taught my little brother JS, and he made this ... by tim1994 on Thursday January 10, 2019 @02:40AM (#18872203)
Also never use Math.pow for squaring numbers (used in the distance function) because it is significantly slower as it is designed for abitrary real exponents, not just integer ones. Cannot be learned soon enough IMO :)

Still a very good job for just a week of coding though.

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Re:Show HN: I taught my little brother JS, and he made this ... by fenomas on Thursday January 10, 2019 @06:56AM (#18873222)
> Also never use Math.pow for squaring numbers (used in the distance function) because it is significantly slower...

Modern JS engines optimize hot functions at runtime - advice like this won't affect actual performance.

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Re:Show HN: I taught my little brother JS, and he made this ... by ghusbands on Thursday January 10, 2019 @09:47AM (#18874170)
This advice is incorrect. Experimenting in the console in both Firefox and Chrome shows that there's not a significant speed difference between the two, even if you make sure you only call a given function with integers <10000.
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Re:Show HN: I taught my little brother JS, and he made this ... by tim1994 on Thursday January 10, 2019 @10:47AM (#18874654)
On my laptop it is about 30% slower (tested with Firefox 64). However I agree, this was not very good advice for someone who just started programming with JS...
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Re:Show HN: I taught my little brother JS, and he made this ... by therein on Thursday January 10, 2019 @06:12AM (#18873037)
Definitely great job. Reminds me of when I taught my physicist friend C and he wrote a raytracer and a game to demo it the next day. I had never witnessed so many trig functions used on a global context.
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Re:Show HN: I taught my little brother JS, and he made this ... by Sean1708 on Thursday January 10, 2019 @06:46AM (#18873178)
Does the JS JIT not handle this? Seems like it would be incredibly trivial...
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