Clojurians Log v2

morning

yesterday

Hello.

I want to make some screencasts showing code and I want to make sure it’s readable. Can you take a quick look at this and tell me whether it works for you: https://carouselapps.wistia.com/medias/p91hhnt9xw

yes I can read it

thomas: mind me asking screen size?

1280x1024

and I can read the browser stuff as well

Great. Thanks.

oi gals/guys. I want to refactor a piece of code doing quite a few transformations on a collection. what i have is basically a thread last threading macro with maps and mapcats I’d like to refactor this to use transducers and thought it should be kinda simple. like use comp instead of the threading macro and don’t pass in the initial input (as map, mapcat should return a transducer when called with one param) and the call the resulting function on my input. does not work tho

any ideas/advice how to compose map transducers if that makes sense?

are you calling into, sequence or transduce?

nope. so I should use something like (into [] (comp … myinput))?

yeah

there’s a little comparison between thread last and transducers

@benedek: interested to know you want to refactor like this

it hardly makes the code more readable

@martintrojer: i did not say it makes sense i am just playing around with something 😉

it can be uglier if you don’t have a performance reason for doing it

which i might be having 😉

Yeah, transducers is clever and all, I’m just left with the big question; why?

it starts looking nicer when you know it’s making a slow thing fast

well, writing web apps. clojure threading macros is never the bottleneck

i basically have a big pipe of transformations on a relatively big/complex data structure. i am looking into ways of making it faster

but yeah i don’t know if i’ve actually needed the perf

Def can make sense if you have lots of steps

things like spark do lots of fusion between mapping functions

initially i thought of transient but quickly realised it is not an easy answer...

for complex stuff with loads of lazyseqs

maybe I find a use for transducers if I look hard enough. But then again, I have a job to do aswell.

I think if i needed the performance i’d already be using something like spark anyway

fair enough. thanks for the comments guys

where big pipelines of transformations are common

Its a art project to confuse haskell-ers right?

I mean, that was its true purpose

In the end it wasn’t so confusing for them

was quite entertaining tho