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A visual demo of Ruby's lazy enumerator

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Re: A visual demo of Ruby's lazy enumerator

#21

Post by robocat »

rossta wrote: post #18
robocat wrote: post #15

Earlier quoted context omitted.

I find horizontal/vertical is usually confusing (not to you obviously). Here is an example: https://www.investopedia.com/terms/h/horizontalanalysis.asp Maybe easier to stick with the lazy/eager wording?

That’s fair. I acknowledge that terms like "horizontal" and "vertical" may be overloaded or even confusing, in this case, if it’s difficult to see the connection with the visuals. This is somewhat part of the risk in trying to explain a concept in a less-than precise way to introduce a new concept.

I love the visuals - they are fantastic at showing the difference.

If the visuals were vertical then the filtering might look more natural because time would be left-to-right and balls would have natural gravity and fall "down" through filters? Code runs top to bottom so I'm guessing it would still be clear.

And putting a number in each of the balls might help clarity too :-)

The only crazy thing is that Haskell lazy is pull (right) whereas Ruby lazy is still push - so the lazy keyword is somewhat confusing but that can't be fixed.

I am not criticising and certainly don't want to make unnecessary work for you. Graphic design and animation are dark arts!

Re: A visual demo of Ruby's lazy enumerator

#22

Post by pansa2 »

So in Ruby, `map` and `select` are eager-by-default, but you can just write `lazy.map().select()` to make the whole chain lazy? That's really nice - much better than Python 2, which was also eager-by-default and you had to change every function call to make it lazy (`map` => `imap`, `filter` => `ifilter`).

Python 3 changed to being lazy-by-default. I assume that improves CPU/memory usage, but in some cases it does have less predictable behaviour. I can see why Ruby, with its goal of "developer happiness", would choose to retain the predictable behaviour of eager-by-default.

Re: A visual demo of Ruby's lazy enumerator

#23

Post by saagarjha »

pansa2 wrote: post #22

So in Ruby, `map` and `select` are eager-by-default, but you can just write `lazy.map().select()` to make the whole chain lazy? That's really nice - much better than Python 2, which was also eager-by-default and you had to change every function call to make it lazy (`map` => `imap`, `filter` => `ifilter`). Python 3 changed to being lazy-by-default. I assume that improves CPU/memory usage, but in some cases it does ha…

Swift does this too, with almost the same syntax. IMO it's the right choice.

Re: A visual demo of Ruby's lazy enumerator

#25

Post by rossta »

fredrikholm wrote: post #16
adsteel_ wrote: post #9

Hm, the CSS and JS don't appear to load for me. Not even a set of tags in the HTML response.

Same here, both on computer and mobile. The rest of the website looks fine.

I have heard a few people mention issues but I haven’t been able to reproduce nor understand the scope of the issue. Any more details you can share? You’re getting HTML but JS or CSS assets aren’t loading, right? What status and headers do you see for static assets?

Re: A visual demo of Ruby's lazy enumerator

#26

Post by rossta »

Exuma wrote: post #20
rossta wrote: post #7

Earlier quoted context omitted.

Thanks for the feedback. I was thinking along those lines but settled on a version that let you toggle between the two. I’ll keep this in mind for next time though. There are probably a lot of fun variations to explore. Since this post seemed to resonate, I may be motivated to try some more experiments.

Your site is broken...

Bummer, I can’t reproduce. Could you share more details?

Re: A visual demo of Ruby's lazy enumerator

#27

Post by whateveracct »

afraca wrote: post #17

When I learned Haskell in college I was blown away by how laziness enables cool things like dealing with infinite lists or more performance even though the UX is exactly the same. (Apparently with Ruby there is the slight hint of adding the lazy method in between) Later I found out laziness in the whole system by default leads to some difficult issues, which quite a few people seem to agree with. Simon Peyton Jones (…

That was SPJ being cute more than an actual indictment of Haskell fwiw. That quote gets misused a lot.

Laziness hasn't killed Haskell's usefulness. However, it is something Haskellers take for granted. I can't tell you how many times they "just turn on -XStrict" and are surprised their program gets slower.

Re: A visual demo of Ruby's lazy enumerator

#28

Post by ryangs »

Java Streams and Kotlin Sequences provide similar iterator capabilities. Iterators are great for this lazy performance but can sometimes be difficult to debug. Especially if you are nesting many iterators, then extracting the underlying collection can be complicated. But necessary in many workflows.
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