i’m not seeing a way to do this which doesn’t involve a branch statment to check if the value is negative or not.

http://www.4clojure.com/problem/44

hmm apparently this has been written about …

luminus vs. pedestal - thoughts?

hey guys, i’m trying to understand how exactly to use java interop with Enums — specifically, I’m trying to use the java.text.Normalizer.Form enum… if I have already imported the java.text.Normalizer, how can I import that ? I thought that using java.text.Normalizer.Form/NFD would’ve done the trick, but it generates a ClassNotFoundException… any suggestions ?

I realize from my latest exercises that many functions in clojure are implemented recursively. Isn't recursion slow?

nvm, figured out it apparently was Normalizer$Form/NFD 🙂

can one set a dependency of a latest version of a library, rather than a named version of it, in leiningen's project.clj? e.g. for having dev-mode stuff like criterium always current

@vitruvia more often then not, you should see recursion implemented with recur, which is tail-call optimized.

but does that make it faster than an iterative alternative or a memoization?

a call to recur turns into a loop

it is iterative

(loop [x 1] (if (< x 10) (recur (inc x)) x)) is effectively for(x = 0; x < 10; x++){};x;

on a byte code level it should be nearly identical

@matan I don't believe so, but in general options like that (wildcards, globbing, implicit imports) are frowned upon in Clojure.

@matan you can get similar things done though with https://github.com/xsc/lein-ancient using lein ancient upgrade

Note that :only/:exclude compose with the :dependencies/:plugins/:all options - to e.g. only upgrade SNAPSHOTs of plugins you'd use:

$ lein ancient upgrade :plugins :only snapshots

@lilactown Pedestal is more of a kind of framework. Not in a project template kind of way, but in that it has a number of new ideas that it provides, such as interceptors. Luminus is much more of a collection of libraries framework. It's like an opinionated collection of libraries that make up a stack that you might have assembled yourself, had you searched for the best combination of libs. You don't have to build your stack that way, but Yogthos has done a lot of that legwork for you and wrapped it up into a nice package.

Luminus has been out for a while now though, so it might provide a number of tricks of its own, but that's the original design difference between the two, IIRC

It's probably possible to rip out a number of pieces of Luminus and cram Pedestal in there, if you really wanted to.

more likely, put parts of luminus into pedestal?

doesn't Luminus bring in ring/compojure? I'd imagine there's a way to replace those bits with pedestal bits, in principle

thanks @john @noisesmith

@john I don't think pedestal uses ring

Might not be a good idea with respect to the other libs in the stack.

it's its own beast

It actually does use a bit of ring, I believe. But yeah, bolting pedestal into luminus' framework might be non-trivial

I moreless bring up the idea to contrast the differences between the two. Might not be a good idea.

oh, it does actually pull in ring-core when I make a new pedestal-app clone

interesting

Guess they didn't want to reinvent what they didn't need to.

also using ring means they can use all the libs implemented as ring middleware

Oh, I meant doesn't Luminus bring in ring/compojure, above, sorry. fixed.

yes, luminus is based on ring and compojure

rgr

I was surprised pedestal was doing it too haha

question in general about frontend lets say i have users that arent supposed to see some options if they are not logged in should i just hide those in css (display: none) (and prevent action from being made if not logged in) then when they do login change css or something else?

is this a question of things being pretty, or securing data they shouldn't be able to access?

if it's an appearance thing, sure, use display:none

but don't even send the apropriate data if it's about security

understood

basically i'd have functon that 'draws' interface for logged out user and same function for logged in with added options

for my app, we don't even send the cljs code until someone logs in - that keeps it simple

prevents leaking implementation details or accidental data via the code

i am forced to do it like this

not my call

if it was up to me i'd do it like you did

thank you very much

@john thanks for the breakdown!

np!