Mornings

morning

disappointed to discover that I had only dreamt that I had fixed an issue with my REPL 😞

I wonder if guava has anything to say about "horrible stream-based messes in Java 8"?

What's the issue?

intermittent - but I was getting an NPE on (reset)

well, intermittent in the sense that sometimes it always happens and sometimes it doesn’t at all

which suggests I’m doing something specific

Potentially a race condition in the updating of state.

it reloads some of the namespaces fine and then borks and can’t load some, and the whole thing falls over

(Removing the stop function from an atom before the stop is called for example!)

if I manually reload the right three namespaces in dependency order then its fine until I hit (reset) again

Ah. A tough one.

the NPE is because a namespace didn’t load

I suspect it has something to do with AOT compilation

Any fully qualified ns in use?

“fully qualified”?

Refresh is fully incompatible with aot. Don't use them in conjunction. A lein clean should solve that.

Some people use app.util/bar without requiring app.util.

okay, so lein clean might sort out the intermittency

that’s good to know

If you've done an AOT (uberjar), lein clean is the answer.

But ensure it's off during development. I'm not sure how to do that in lein, skip-aot metadata maybe?

mostly I steer as far from AOT as possible - but I’m AOTing the whole app for the uberjar in an attempt (that seems successful) to speed up start up time

for the jar I have one ns with :gen-class and a main- function

Absolutely a fine use of aot. Bad for dev though. Gotta turn it off & clean between uses.

maybe a clean is all it will need if I’ve jarred it recently

Potentially, depends on how you've setup your project.clj

so do I need to explicitly disable AOT?

I know we do on our lein projects. I've not investigated whether it's still necessary though.

the only reference to aot in my project.clj is :uberjar {:aot :all… in my :profiles

You may need an :aot :none at the top level / dev profile. But I'm again, uncertain. Try clean. If not, play with that. But I imagine you'd see if aot was happening when you did lein repl

If you get really desperate, make sure it still happens if you don't hook up your editor. Sometimes caches can be problematic, particularly on big projects.

okay thanks, that gives me lots to go on if it recurs

it certainly often feels (not just with this problem) that AOT and REPLs are not good friends

Yep!

Might be worth paying close attention to what is reloading. Make sure there's nothing external in there.

“external”?

E.g. Bidi.ring being reloaded.

As opposed to myapp.foo

morning

oic

on a lighter note I’ve been doing some ClojureScript recently and I think it should come with an addictiveness warning - it’s sooooo much fun!

Did you start that around the same time as the npe started?

Where do you put your compiled assets?

Re: on knowing more about the content of the clj std lib, reasons, opportunities and suggestions 🙂 https://labs.uswitch.com/an-introduction-to-the-clojure-standard-library/

Ps. that's really our office library! 🙂

Lucky!

That's pretty cool

https://twitter.com/resi_analyst/status/847028962454835201

Thought you folks living in the big smoke would be interested...

hmmm nice one

(interactive version) https://dancooksonresearch.carto.com/u/dancookson/viz/5eb8c336-1555-11e7-9e20-0e3ebc282e83/embed_map

Nice - now can you do price per area per commute time? 🙂

And extend it to us hicks who live outside the M25 🙂

korny: I didn’t do the visualisations, and have never met the person who did… but we did do the data publishing work for the EPC data release which made this possible ( https://epc.opendatacommunities.org/ )

so you can access the data and make your own 🙂

🙂

Nice - by the way, is there any public data around property boundaries and the like? In Aus there was an awesome online map where you could browse all open property data - right down to individual property boundaries. It'd be handy to have something similar here...

The aus one is at http://services.land.vic.gov.au/maps/pmo.jsp (at least for Victoria)

i think some people at the land registry were intending to publish that as open data

but i also heard the land registry was being sold off to a private firm

so /shrug

I guess as I'm working in http://gov.uk I should ask around here...

rickmoynihan that's your publication? nice one 😄

korny lots more data available to gov't people than generally to us who rely on the OGL

otfrom: well we built the app, prepped the data, and host and maintain it. Had to publish the data as is, so couldn’t clean it etc… the publication and data is the DCLGs.

well, by publication, I mean that you liberated it from DCLG's data dungeon. 🙂

that’s one way of putting it… I won’t comment on the accuracy of that statement though 🙂

Cool visualistion! In the bottom half of the map there’s three super expensive satellites? What might they be?

They seem very out on their own.

anyone know anything about java-2d in-memory representation ? i'm seeing a 5k^2 image OOM a 1GB jvm... though a trivial estimate would put that image unpacked to 200MB

the image is 5k x 5k pixels?

how many bytes per pixel?

assuming 4 bytes per pixel:

(* 4 15000 15000)
=> 900000000

(if you’re using a BufferedImage somewhere then this may explain: https://docs.oracle.com/javase/7/docs/api/java/awt/image/BufferedImage.html)

yeah, the image was 5k x 5k px

i assumed 8 bytes per pixel - 4x16-bit color chans, giving me ~200MB (i think you estimated a 15k^2 image)

anyway, looks like resizing the image to a few different resolutions was requiring ~600MB in total... works fine on a 2GB jvm

Found this quote I hadn't seen before that struck a chord with the way I need tests. > The real value of tests is not that they detect bugs in the code but that they detect inadequacies in the methods, concentration, and skills of those who design and produce the code. - Tony Hoare

👋

I’d say that’s true of the process of creating good tests, but not a property of tests themselves

although i suppose being reminded of what something is supposed to do after you’ve changed it would allow you to have less concentration and skill