2015-12-11
| 00:07 | lambda-11235 | Is there any way to get that map from an exception? |
| 00:12 | kenrestivo | the only thing more ridiculous than java logging is java PKI management |
| 00:14 | TEttinger | kenrestivo: what about that restaurant in Japan that has monkey waitresses |
| 00:14 | TEttinger | I mean it's pretty ridiculous |
| 00:25 | ridcully | i bet there is some relation |
| 00:52 | devn | lambda-11235: https://clojuredocs.org/clojure.core/ex-info |
| 00:57 | devn | ,(ex-data (try (/ 1 0) (catch Exception e (ex-info "D'oh!" {:cause (.getMessage e) :other {:stuff "here"}})))) |
| 00:57 | clojurebot | devn: Cool story bro. |
| 00:57 | devn | &(ex-data (try (/ 1 0) (catch Exception e (ex-info "D'oh!" {:cause (.getMessage e) :other {:stuff "here"}})))) |
| 00:57 | devn | ,(ex-data (try (/ 1 0) (catch Exception e (ex-info "D'oh!" {:cause (.getMessage e) :other {:stuff "here"}})))) |
| 00:57 | clojurebot | devn: Cool story bro. |
| 00:58 | lambda-11235 | devn: I meant get the map from any exception like 1.7 print does, not just package data with an exception. |
| 01:01 | lambda-11235 | ex-info is still cool, though I haven't seen it used often. |
| 01:01 | devn | ,(try (/ 1 0) (catch Exception e (ex-info "D'oh!" {:cause (.getMessage e) :other {:stuff "here"}}))) |
| 01:01 | clojurebot | devn: Cool story bro. |
| 01:02 | devn | lambda-11235: run that in your REPL |
| 01:02 | devn | that's exactly what you're looking for, i'm pretty sure |
| 01:11 | lambda-11235 | devn: Not exactly. I had to look through the clojure source code, but I found it. It was Throwable->map. |
| 03:17 | Trioxin | well, immutability seemed ridiculous to me at first but now I've got it and it's awesome. |
| 03:19 | Trioxin | now, this notion of not entangling things sort of brings me to the Unix philosophy. Would that be a sufficient analogy? |
| 03:30 | ridcully | do you mean the "do one thing and do it great"? |
| 03:35 | Trioxin | ridcully, where hickley was talking about not entangling things within your software. I suppose not having objects and classes helps a lot with that but it sounded like he was also talking about programming practices within clojure, in some way having your functions and components not depend on the others so much. Maybe there's a good tutorial for the best ways to model your software in Clojure? |
| 03:36 | Trioxin | I'm coming from OOP so the last thing I want to do is incorrectly implement clojure based on what I'm used to. |
| 03:43 | ridcully | i dont know one. same as the clojure universe don't has many "frameworks" and favours composition via libraries you do on your own, i'd expect only guidelines out there or "common wisdom" |
| 03:43 | ridcully | and you most likely will end up doing things the wrong way - that's part of learning |
| 03:45 | Trioxin | ridcully, so braveclojure isn't going to turn on all the light bulbs? |
| 03:46 | ridcully | i can not comment on that. i have only read parts of the website some time ago |
| 03:47 | Trioxin | hmm. I'll come back when I've got it ALL down better via several tutorials. |
| 03:47 | Trioxin | with those questions |
| 03:48 | ridcully | i think some bulbs will light up by doing |
| 03:48 | Trioxin | that too |
| 03:49 | ridcully | there will be some moments when you jump off your chair with "yeah i did it" or "can't believe it's that easy" |
| 03:51 | Trioxin | well I can see that happening and I can also see clojure beings so flexible as to be giving me plenty of rope to hang myself |
| 03:52 | ridcully | sure. there will be same amount of you jumping off your chair, pick it up, throw it out the window because that trillion line exception makes no sense at all ;) |
| 06:13 | beaky | ehllo |
| 06:26 | powered | has development on Counterclockwise stopped or something? |
| 06:55 | BRODUS | how do i deconstruct a vector argument to a function such that i have the first value of the vector and the remainder of the vector as named values? |
| 06:56 | luma | (defn foo [[x & xs]] ... ) |
| 06:58 | BRODUS | luma: thx |
| 07:21 | marchelzo | what is the equivalent pattern in clojure to haskell's (c:cs)? |
| 07:21 | ARM9 | clojure doesn't have pattern matching like haskell, but you can destructure a list/vector/string to a head and a rest with [x & xs] in most binding forms |
| 07:22 | marchelzo | is 'match' just like ad-hoc pattern matching with macros? |
| 07:23 | ARM9 | ,(let [[x & xs] [1 2 3]] (cons x xs)) |
| 07:23 | clojurebot | (1 2 3) |
| 07:24 | ARM9 | what match? |
| 07:24 | marchelzo | core.match |
| 07:24 | ARM9 | right, that's a library |
| 07:24 | ARM9 | not actually part of the core language afaik |
| 07:25 | marchelzo | so if I wanted to write a function that handled two cases: the empty sequence, and [a & as], what is the idiomatic way to do that? |
| 07:25 | ARM9 | yeah it's probably some macro soup |
| 07:25 | ARM9 | with or without core.match? |
| 07:25 | marchelzo | without |
| 07:26 | MJB47 | what do you mean by empty sequence? |
| 07:26 | MJB47 | as in no arguments to the function? |
| 07:26 | ARM9 | an empty seq |
| 07:26 | marchelzo | I hope sequence is the right word |
| 07:26 | marchelzo | maybe I mean list |
| 07:26 | ARM9 | (and (empty? []) (empty? "") (empty? '())) |
| 07:26 | ARM9 | ,(and (empty? []) (empty? "") (empty? '())) |
| 07:26 | clojurebot | true |
| 07:27 | ARM9 | no seq is probably what you want |
| 07:27 | ARM9 | clojure abstracts several types of collections as sequences |
| 07:27 | marchelzo | and in the case that it isn't empty, I'd use 'let' to destructure it? |
| 07:28 | ARM9 | (if-let [[x & xs] []] x) |
| 07:28 | ARM9 | god I always forget the , |
| 07:34 | ARM9 | actually that might not be what you want, you might have to manually check the emptiness of the seq without something like core.match |
| 07:36 | luma | ,(if-let [[x & xs] (seq [])] :match :no-match) |
| 07:36 | clojurebot | :no-match |
| 07:38 | ARM9 | ,(if-let [[x & xs] (seq [1 2 3])] (cons x xs) (iterate #(+ % 1) 1)) |
| 07:38 | clojurebot | (1 2 3) |
| 08:27 | douglarek | , (identity "s") |
| 08:27 | clojurebot | "s" |
| 09:13 | magthe | I'm playing around with ring, and confusingly my :body attribute in requests has different type depending on if the request is sent using curl or from the browser... so question now is where do I read up on how to work with org.eclipse.jetty.server.HttpInputOverHTTP? |
| 09:49 | justin_smith | no matter what, it should implement InputStream, and you can use a ring middleware to pre-process, or slurp it to get a string if you want to process it yourself |
| 10:58 | nanuko | does anyone have experience with quickie? |
| 10:59 | vvgomes | Is there any function to flip arguments of a function? |
| 10:59 | powered | reverse |
| 10:59 | vvgomes | let me try |
| 11:00 | powered | something like (fn [f] (fn [& args] (apply f (reverse args)))) |
| 11:00 | justin_smith | ,(defn flip [f] (fn [& args] (apply f (reverse args)))) |
| 11:00 | clojurebot | #'sandbox/flip |
| 11:00 | justin_smith | ,((flip /) 3 2) |
| 11:00 | clojurebot | 2/3 |
| 11:01 | powered | haha, I thought of the same solution as an expect clojure user |
| 11:01 | justin_smith | ,((flip map) (range) inc) |
| 11:01 | clojurebot | (1 2 3 4 5 ...) |
| 11:02 | vvgomes | powered: I don't think reverse does the job |
| 11:03 | powered | vvgomes, look at the function justin_smith wrote earlier |
| 11:03 | vvgomes | yes, I could write that function... but I was looking for an existing one :/ |
| 11:04 | powered | there's no core function that does that |
| 11:04 | vvgomes | :/ thanks anyway |
| 11:04 | justin_smith | ,(defn shuffle-flip [f] (fn [& args] (apply f (shuffle args)))) |
| 11:04 | clojurebot | #'sandbox/shuffle-flip |
| 11:05 | justin_smith | pretty-much-useless |
| 11:05 | justin_smith | ,((shuffle-flip str) "pretty" "much" "useless") |
| 11:05 | clojurebot | "muchprettyuseless" |
| 11:07 | maddagaska | Hi, I'm trying to do something with code inspired by (copy-pasted from, mostly) less-awful-ssl but any time I try to use an SSLContext without a Key manager it gives me an exception: java.lang.IllegalArgumentException: array element type mismatch, compiling |
| 11:07 | maddagaska | less-awful-ssl is here, and the highlighted line is the one I'm changing (to (.init nil) https://github.com/aphyr/less-awful-ssl/blob/master/src/less/awful/ssl.clj#L130 |
| 11:08 | vvgomes | powered justin_smith I'm still trying to think of a point free version for that... |
| 11:08 | powered | 'point free'? |
| 11:08 | vvgomes | you know, without fn or defn |
| 11:08 | justin_smith | (comp (partial apply f) reverse list) |
| 11:08 | vvgomes | https://wiki.haskell.org/Pointfree |
| 11:09 | vvgomes | oh, let me try that.. |
| 11:09 | maddagaska | Is there anything obvious that I'm doing wrong? |
| 11:09 | justin_smith | ((comp (partial apply /) reverse list) 3 2) |
| 11:09 | justin_smith | ,((comp (partial apply /) reverse list) 3 2) |
| 11:09 | clojurebot | 2/3 |
| 11:09 | justin_smith | not totally point-free - you need to get the function into the middle there |
| 11:10 | powered | what's so cool about point free? |
| 11:11 | justin_smith | powered: it's a cool mental exercise, in haskell it can avoid extraneous creation of new lambdas at runtime |
| 11:11 | vvgomes | plus, it makes function composition a lot easier |
| 11:12 | powered | I never use function composition on higher level functions though |
| 11:12 | justin_smith | I mean it creates a function that takes the same args, and returns the same value... but maybe conceptually it makes the building blocks its made of easier to rearrange? |
| 11:13 | BRODUS | it makes clojure code more readable if youre using point free functions with '->>' |
| 11:54 | TimMc | moar liek point less amirite |
| 11:55 | wink | I am confused. anyone got a hint? source: {:foo "f" :bar "b"} and what I need: [{:k :foo/"foo" :v "f} {:k :bar/"bar" :v "b"}] |
| 11:56 | TimMc | That's an input/output pair? |
| 11:56 | TimMc | What is :foo/"foo", a weird keyword? |
| 11:56 | wink | I don't care if :foo or "foo" |
| 11:57 | TimMc | ah |
| 11:57 | TimMc | map over the map |
| 11:57 | wink | what I need: map to vec/list "of named tuples" |
| 11:57 | TimMc | ,(for [pair {:foo "f" :bar "b"}] pair) |
| 11:57 | clojurebot | ([:foo "f"] [:bar "b"]) |
| 11:58 | wink | oh wow. thanks. that's what I get for never using for |
| 11:58 | TimMc | so instead of that last "pair" you can take apart the pair and make your :k :v map |
| 11:58 | TimMc | (for [[k v] ...] ...) |
| 11:58 | TimMc | always use for :-) |
| 11:59 | TimMc | wink: But (map #(...) ...) would work just fine here. |
| 11:59 | MJB47 | ,(map (fn [[k v]] {:k k :v v}) {:foo "f" :bar "b"}) |
| 11:59 | clojurebot | ({:k :foo, :v "f"} {:k :bar, :v "b"}) |
| 11:59 | wink | yup that's better |
| 11:59 | wink | thanks a lot! |
| 11:59 | wink | brain too dead for this on a Friday night |
| 12:00 | luma | mapping an anonymous function is usually a sign that you should use for |
| 12:01 | MJB47 | it is slightly shorter as for here |
| 12:01 | MJB47 | ,(for [[k v] {:foo "f" :bar "b"}] {:k k :v v}) |
| 12:01 | clojurebot | ({:k :foo, :v "f"} {:k :bar, :v "b"}) |
| 12:02 | MJB47 | which is more readable, up to you |
| 12:03 | wink | I like the for one more, but the other one makes more sense to understand why I failed |
| 12:03 | wink | if in doubt, destructure |
| 12:09 | blischalk | Anyone familiar with Quartzite know how to prevent a job from being triggered if there is already another job in progress? |
| 12:15 | nickmbailey | it seems that 'lein uberjar' doesn't respect repositories configured in ~/.lein/profiles.clj, anyone run into that and know a fix? |
| 12:25 | justin_smith | nickmbailey: profiles.clj is not for things you want to have in your jar - it's for things you use locally but are not part of the codebase |
| 12:26 | justin_smith | if they belong in a project, explicitly add them to the project.clj |
| 12:27 | nickmbailey | well the reason its in profiles.clj is because the repo has auth on it and i don't want to check that into git but fair enough |
| 12:28 | nickmbailey | if i put the repository in the project.clj it will work? |
| 12:28 | nickmbailey | justin_smith: ^ |
| 12:28 | justin_smith | yeah - I guess you need some mechanism for separating the auth from the jar though? |
| 12:30 | nickmbailey | well you can set up repository credentials i guess but you have to like use gpg or something |
| 12:30 | nickmbailey | its rather frustrating |
| 12:32 | justin_smith | right - but if you don't want creds in the repo, it seems just as bad to put them in the jar |
| 12:33 | nickmbailey | i'm confused, why would they be in the jar? |
| 12:33 | justin_smith | project.clj ends up in the jar |
| 12:33 | nickmbailey | oh right |
| 12:34 | nickmbailey | yeah i think i have to set up ~/.lein/credentials.clj.gpg |
| 12:34 | nickmbailey | so that i define the repo url in project.clj but not the creds |
| 12:34 | nickmbailey | not really sure if i understand why uberjar specifically ignores profiles.clj |
| 12:35 | nickmbailey | but i'm probably just grumpy |
| 12:35 | justin_smith | nickmbailey: profiles.clj is for things you wouldn't put in a project - like dev utilities |
| 12:36 | justin_smith | it's not meant as "these jars belong in all my uberjars" |
| 12:36 | nickmbailey | well uberjar is already smart enough to only pull in the deps of the project |
| 12:37 | nickmbailey | but yeah ok |
| 12:37 | nickmbailey | i wonder if I actually have to use gpg |
| 12:37 | nickmbailey | thats the annoying part |
| 12:37 | justin_smith | you can put the creds in an env var |
| 12:37 | justin_smith | it depends on how important opsec is |
| 12:38 | nickmbailey | not very, this is a temporary situation where i have to build from an internal repo |
| 12:38 | justin_smith | it's not like a var in your env is less secure than a file that is readable by any other user on your computer |
| 12:38 | nickmbailey | and i have a team of 15 devs that i don't want to make go through some complicated process just to build the project |
| 12:39 | justin_smith | nickmbailey: I trained my team to use a creds.gpg - they ended up turning on the box OSX popped up "remember the password for this gpg keychain" and now I don't even know if they realize they are using gpg any more |
| 12:40 | justin_smith | whenever they use our private repo, lein asks for the decrypt, gpg-agent talks to their osx keychain, and lein gets the decrypted data, with no interaction on their part |
| 12:41 | nickmbailey | yeah but this has to build on jenkins which would be deb boxes, centos boxes, etc |
| 12:41 | nickmbailey | i'm definitely grumpy |
| 12:41 | justin_smith | nickmbailey: that's where the env var option comes into play |
| 12:41 | justin_smith | on a machine where physical access is less of a risk, putting it in an env var is less of an issue |
| 12:42 | nickmbailey | i suppose |
| 12:42 | nickmbailey | at least most devs run osx |
| 12:43 | nickmbailey | i guess the linux devs can handle figuring out gpg |
| 12:43 | nickmbailey | sigh |
| 12:43 | justin_smith | gpg-agent isn't much different under ubuntu (depending on desktop environment of course - if you want the smooth you are already using gnome, if you want the cranky devops way you aren't etc.) |
| 12:48 | nickmbailey | justin_smith: yeah |
| 12:48 | nickmbailey | thanks for the help btw :) |
| 12:48 | nickmbailey | do you know what the env vars are off the top of your head |
| 12:53 | nickmbailey | oh i see it in the help nvm |
| 12:53 | nickmbailey | i am unsure how i mix the two though, if i put :creds :gpg in project.clj, then it won't look in the env on jenkins |
| 13:12 | justin_smith | nickmbailey: your local dev will be using the :dev profile, the uberjar process on jenkins will be using the :uberjar profile |
| 13:18 | nickmbailey | ah right, duh |
| 13:18 | nickmbailey | thanks |
| 13:22 | nickmbailey | filed a ticket to help make some of the creds error cases clearer fwiw |
| 13:22 | nickmbailey | https://github.com/technomancy/leiningen/issues/2039 |
| 13:39 | nickmbailey | (inc justin_smith) |
| 13:40 | nickmbailey | didn't clojurebot used to respond to that? |
| 13:42 | justin_smith | lazybot did |
| 13:42 | WorldsEndless | I heard that .cljc was supposed to be clojure -> C compiled, but I often see it seeming to mean "non-CLJS". Is there a standard? |
| 13:43 | justin_smith | WorldsEndless: .cljc allows multiple compiler targets in one file. It has nothing to do with C |
| 13:44 | WorldsEndless | justin_smith: ah... do you have an example of when .cljc would be better than .clj? |
| 13:44 | justin_smith | afaik it only does clj / cljs and maybe clr-clj |
| 13:44 | WorldsEndless | Or how you can determine whether your file (with required libs) qualifies as cljc? |
| 13:45 | justin_smith | WorldsEndless: sure, when you want to have the same functions available in clj and cljs code. For example in my app we have a cljc lib for encoding and parsing a custom query parameter scheme that allows edn, we want to be able to create and parse the parameter strings from both the frontend and the backend |
| 13:45 | WorldsEndless | So does lein handle cljc differently, or is it just for developer semantics? |
| 13:46 | justin_smith | the clojure compiler handles it differently |
| 13:46 | justin_smith | lein doesn't even need to know how it works, if you have a cljc file in classpath, clojure and clojurescript both know how to load it |
| 13:48 | WorldsEndless | Ah. That's cool |
| 13:49 | WorldsEndless | I'm surprised not to have seen that mentioned in any of the various Clojure books |
| 13:49 | WorldsEndless | And not easily findable by search engine, either |
| 13:49 | postpunkjustin | WorldsEndless: cljc is a pretty new thing, after (nearly?) all of the books came out |
| 14:03 | WorldsEndless | postpunkjustin: Thanks. Are you related to justin_smith ? |
| 14:03 | postpunkjustin | only as co-Justins |
| 14:04 | postpunkjustin | and we attend the same Clojure meetup here in Portland |
| 14:04 | justin_smith | WorldsEndless: we've been seen in the same room multiple times |
| 14:04 | postpunkjustin | it's true |
| 14:04 | WorldsEndless | Just making sure postpunkjustin is not referring to the name justin_smith :) |
| 14:04 | postpunkjustin | sorry for any confusion |
| 14:05 | WorldsEndless | I am being tragically disabused of the notion that Clojure uberjar deployment would be a breeze... |
| 14:05 | justin_smith | WorldsEndless: but it is a breeze... |
| 14:05 | WorldsEndless | I can "lein run" on both my local and AWS (identical codebase). I can "lein uberjar" and "java -jar new-jar" local. However, the same jar will NOT run on AWS, and I also can't "lein uberjar" on AWS. |
| 14:06 | WorldsEndless | It's driving me crazy. |
| 14:06 | justin_smith | WorldsEndless: my favorite trick is to aot compile nothing, and when running the uberjar launch clojure.main as the main class, telling it to require and run your primary ns |
| 14:06 | justin_smith | WorldsEndless: describe "will NOT run" in more detail? |
| 14:07 | WorldsEndless | On AWS: java -jar turbo-tenure.jar |
| 14:07 | WorldsEndless | Exception in thread "main" java.lang.ExceptionInInitializerError |
| 14:07 | justin_smith | WorldsEndless: do you have a full stack trace somewhere? |
| 14:07 | WorldsEndless | What's the simplest way to get around the "... 104 more" message and get a full trace? |
| 14:07 | justin_smith | my first suspicion is java version, plus some compiled java deps that don't like that java version |
| 14:08 | WorldsEndless | Ok. that was my first suspicion also, because I haven't been able to get java 1.8 on SLES |
| 14:08 | justin_smith | what about 'java -cp turbo-tenure.jar clojure.main" then manually require your namespace? |
| 14:08 | justin_smith | then you can use (pst) etc. |
| 14:10 | justin_smith | if you run clojure.main, all that needs is java 6 |
| 14:10 | WorldsEndless | justin_smith: Clearly your java-fu is beyond mine. Do I need to write new code for that, or all from the CL? |
| 14:10 | justin_smith | WorldsEndless: that's a command line you can run |
| 14:10 | justin_smith | it gives you a clojure repl |
| 14:11 | WorldsEndless | Oh, cool |
| 14:11 | justin_smith | from that repl (require 'my-ns) (in-ns 'my-ns) etc. |
| 14:11 | WorldsEndless | Ok, that has helped me narrow things down |
| 14:12 | WorldsEndless | My suspicion is that it has to do with the environ module, which seems to break things when I try my app on new systems |
| 14:12 | WorldsEndless | <ec2-user> ~/ 18:58$ java -cp turbo-tenure.jar clojure.main |
| 14:12 | WorldsEndless | Clojure 1.7.0 |
| 14:12 | WorldsEndless | user=> (require 'turbo-tenure.core) |
| 14:12 | WorldsEndless | NullPointerException com.mongodb.ConnectionString.<init> (ConnectionString.java:195) |
| 14:13 | WorldsEndless | ^^ was actually somewhere in the stack trace, too, but not as clear |
| 14:13 | justin_smith | could this be because the required mongo connection info isn't being provided properly / isn't being found? |
| 14:13 | WorldsEndless | That's what I'm guessing, but I'm not sure why. The env vars are defined in project.clj, so should be available |
| 14:14 | justin_smith | WorldsEndless: java -jar ... is not governed by project.clj at all |
| 14:15 | justin_smith | project.clj can set properties for dev time, when you are running lein, but does nothing when running your uberjar |
| 14:15 | WorldsEndless | But shouldn't it be reflected in the output of "lein uberjar"? |
| 14:15 | justin_smith | what would it output? |
| 14:15 | justin_smith | there's no such mechanism for environ - you need to manually set those things for environ to work on prod |
| 14:15 | WorldsEndless | My project has the following under :profiles: |
| 14:15 | WorldsEndless | {:uberjar {:omit-source true |
| 14:15 | WorldsEndless | :env {:database-url "mongodb://127.0.0.1/turbo_tenure" |
| 14:15 | WorldsEndless | :production true} |
| 14:16 | WorldsEndless | |
| 14:16 | justin_smith | WorldsEndless: general assumption is that you would be using 12-factor style deployment, where you put the config in the environment vars |
| 14:16 | justin_smith | WorldsEndless: and the project.clj settings do nothing when running your uberjar |
| 14:16 | justin_smith | you need to provide the credentials va the environment |
| 14:16 | WorldsEndless | Hmm... I thought they'd end up hard-coded in to the uberjar |
| 14:16 | justin_smith | or via java system properties you can set on the java command line if you prefer |
| 14:17 | justin_smith | WorldsEndless: nope, there's no such mechanism |
| 14:17 | WorldsEndless | justin_smith: Good to know |
| 14:17 | WorldsEndless | specifying extra "enviro" stuff assisted with dev on multiple systems, but cleary doesn't help with running your jar |
| 14:25 | slester | what's the max length for a string? I seem to be stack overflowing |
| 14:26 | justin_smith | slester: the jvm does not store strings on the stack |
| 14:26 | justin_smith | slester: this is more likely happening in your code handling the string |
| 14:26 | slester | hmmm! |
| 14:26 | justin_smith | it's one of the notorious java design decisions, putting nearly everything in the heap |
| 14:26 | slester | justin_smith, http://hastebin.com/xowanaqaho.lisp |
| 14:27 | slester | it's for advent of code so... |
| 14:27 | slester | not too much help :D |
| 14:27 | slester | the string gets really large |
| 14:27 | MJB47 | you should refactor it |
| 14:28 | MJB47 | to use loop recur |
| 14:28 | MJB47 | at a minimum |
| 14:28 | MJB47 | which implements TCO |
| 14:28 | justin_smith | slester: yeah, say calling say is likely what causes the SO |
| 14:28 | justin_smith | it should be as simple as changing "say" on line 11 to "recur" |
| 14:28 | MJB47 | also you might want to use (seq input) instead of /split |
| 14:28 | slester | oh, I see |
| 14:28 | slester | I don't quite understand the difference between recur & calling the function |
| 14:29 | MJB47 | recur uses some magic |
| 14:29 | MJB47 | to not blow the stack |
| 14:29 | justin_smith | slester: calling the function uses more stack |
| 14:29 | justin_smith | slester: recur is basically just a loop, no extra stack usage |
| 14:29 | slester | ooh, well it seems to be working! or going further anyway. |
| 14:30 | slester | thanks for that tip |
| 14:30 | MJB47 | you could have also used doseq for this |
| 14:30 | justin_smith | MJB47's idea for using seq / chars instead of split / one letter strings is a good one too |
| 15:18 | fsjhfkjdhf | hi why can't i sort a list by type? (sort-by type [1 :a 2 :b 3 :c]) |
| 15:18 | fsjhfkjdhf | i get the error: java.lang.ClassCastException: null |
| 15:19 | amalloy | (doc sort-by |
| 15:19 | amalloy | (doc sort-by) |
| 15:19 | clojurebot | #<RuntimeException java.lang.RuntimeException: EOF while reading> |
| 15:19 | clojurebot | "([keyfn coll] [keyfn comp coll]); Returns a sorted sequence of the items in coll, where the sort order is determined by comparing (keyfn item). If no comparator is supplied, uses compare. comparator must implement java.util.Comparator. If coll is a Java array, it will be modified. To avoid this, sort a copy of the array." |
| 15:19 | amalloy | ,((sort-by type [1 :a 2 :b 3 :c])) |
| 15:19 | clojurebot | #error {\n :cause "java.lang.Class cannot be cast to java.lang.Comparable"\n :via\n [{:type java.lang.ClassCastException\n :message "java.lang.Class cannot be cast to java.lang.Comparable"\n :at [clojure.lang.Util compare "Util.java" 153]}]\n :trace\n [[clojure.lang.Util compare "Util.java" 153]\n [clojure.core$compare invokeStatic "core.clj" 808]\n [clojure.core$compare invoke "core.clj" -1... |
| 15:20 | fsjhfkjdhf | lol see what i mean |
| 15:21 | justin_smith | ,(compare String Character) |
| 15:21 | clojurebot | #error {\n :cause "java.lang.Class cannot be cast to java.lang.Comparable"\n :via\n [{:type java.lang.ClassCastException\n :message "java.lang.Class cannot be cast to java.lang.Comparable"\n :at [clojure.lang.Util compare "Util.java" 153]}]\n :trace\n [[clojure.lang.Util compare "Util.java" 153]\n [sandbox$eval93 invokeStatic "NO_SOURCE_FILE" 0]\n [sandbox$eval93 invoke "NO_SOURCE_FILE" -1]\... |
| 15:21 | justin_smith | that's the error |
| 15:21 | justin_smith | ,(sort-by (comp str type) [1 :a 2 :b 3 :c []]) |
| 15:21 | clojurebot | (:a :b :c [] 1 ...) |
| 15:21 | justin_smith | as long as every type prints uniquely that should be good enough? |
| 15:22 | fsjhfkjdhf | hooray thank you! |
| 15:22 | fsjhfkjdhf | (trying to solve 4clojure problem 50 ;)) |
| 15:23 | justin_smith | fsjhfkjdhf: in case it's not clear, that's getting each type, then converting to string, since you can compare and sort strings (unlike classes) |
| 15:24 | fsjhfkjdhf | yeah it makes sense thank you :D |
| 15:25 | fsjhfkjdhf | hooray beat 50 |
| 15:26 | fsjhfkjdhf | oh whoops |
| 15:26 | fsjhfkjdhf | group-by == sort and then partition by.. oh well |
| 15:27 | justin_smith | fsjhfkjdhf: my solution to that one - (comp vals (partial group-by type)) |
| 15:27 | fsjhfkjdhf | yeah i see that |
| 15:27 | fsjhfkjdhf | i used #(partition-by (comp str type) (sort-by (comp str type) %)) |
| 15:28 | justin_smith | fsjhfkjdhf: the partition-by can still use type |
| 15:28 | justin_smith | it's only the sort that needs (comp str type) |
| 15:28 | fsjhfkjdhf | oh right yeah |
| 15:28 | justin_smith | since partition-by only needs to compare = or not |
| 15:28 | fsjhfkjdhf | mmhm |
| 15:29 | justin_smith | fsjhfkjdhf: so you got double the learning experience on one puzzle by finding two approaches |
| 15:29 | fsjhfkjdhf | haha yeah that seems to be the case with almost all of them |
| 15:29 | fsjhfkjdhf | "finally got it working and ... oh it can be solved with this one function" |
| 15:30 | justin_smith | fsjhfkjdhf: reduce never made sense to me until I made my own crappy version |
| 15:30 | justin_smith | and then I was like - oh wait, that's what reduce is for? it makes sense now! |
| 15:30 | fsjhfkjdhf | yeah i'm still a bit unsure about reduce so i try to use it for a lot of solutions so i can practice it |
| 15:30 | justin_smith | fsjhfkjdhf: I even made my own silly message passing / data flow system before I groked core.async |
| 15:30 | fsjhfkjdhf | hehe |
| 15:31 | justin_smith | making the bad version is one way to learn how the good version works |
| 15:32 | justin_smith | fsjhfkjdhf: the big game changers with reduce are: reduced - return this value immediately skipping the other input, and the fact that you can pass a data structure as your accumulator in order to effectively have multiple accumulators |
| 15:32 | fsjhfkjdhf | yeah it seems like just about anything can be done with reduce |
| 15:32 | fsjhfkjdhf | since it maintains state between operations |
| 15:32 | justin_smith | as long as your input is a collection, sure |
| 15:33 | justin_smith | reduce is what many people expect for to be (based on what for is in C / java) |
| 15:34 | justin_smith | fsjhfkjdhf: but it does something better than maintaining state - it allows the explicit propagation of state, rather than implicit state mutation :) |
| 15:35 | fsjhfkjdhf | yeah so you can have state and purity too pretty cool |
| 15:35 | fsjhfkjdhf | omg finally i passed my friend |
| 15:35 | fsjhfkjdhf | me and two other people are learning clojure and racing to the end of this 4clojure website |
| 15:36 | justin_smith | hah, nice, I still haven't done all the problems there |
| 15:36 | fsjhfkjdhf | what number are you on? |
| 15:36 | justin_smith | hmm... |
| 15:37 | one | if i have a function that uses variadic overloads can i also include keyword arguments? |
| 15:37 | one | i keep getting errors |
| 15:37 | one | Can't have more than 1 variadic overload |
| 15:37 | __ior | i'm also working throuh 4clojure, it's pretty great, though i wish questions that came after "not allowed to use core.somefunction" actually required core.thefunctionyoujustrewrote |
| 15:38 | justin_smith | fsjhfkjdhf: rank 344, 140 problems solved, user name "noisesmith" |
| 15:38 | __ior | that way you could really get the feel for the core libraries |
| 15:38 | fsjhfkjdhf | ! quite a bit |
| 15:39 | justin_smith | the 16 I have left are tough ones though |
| 15:40 | one | no? |
| 15:40 | clojurebot | no is tufflax: there was a question somewhere in there, the answer |
| 15:41 | justin_smith | one: a function can't have more than 1 variadic overload- how would clojure know which one of them to call? |
| 15:43 | one | is there any way to force keyword arguments then? |
| 15:43 | one | with overloads |
| 15:44 | one | because the alternative is making like 30 changes to everything that calls this fucntion |
| 15:45 | one | is there a way to assign default values to & [x y z]? |
| 15:45 | one | because that would work too |
| 15:45 | one | possible |
| 15:45 | one | possibly |
| 15:45 | ARM9 | ((fn[& {:keys [a b c]}] [a b c]) :a 1 :b 2 :c 3) |
| 15:45 | ARM9 | ,((fn[& {:keys [a b c]}] [a b c]) :a 1 :b 2 :c 3) ; for posterity |
| 15:46 | clojurebot | [1 2 3] |
| 15:46 | one | but i need the non keyword arguments to have defaults |
| 15:46 | one | as well as the keyword arguments |
| 15:46 | ARM9 | you can set keyword arguments to defaults at least, not sure about other arguments |
| 15:46 | one | yea |
| 15:47 | one | the way its done in the code is basically |
| 15:47 | ARM9 | ,((fn[& {:keys [a b c] :or {c 42}}] [a b c]) :a 1 :b 2) |
| 15:47 | clojurebot | [1 2 42] |
| 15:48 | one | (defn x ([a] (x a 0)) ([x y])) |
| 15:48 | one | but far larger |
| 15:50 | justin_smith | one: clojure.core makes separate arities for everything up to 4 args or so typically, then finally implements varargs after that |
| 15:50 | justin_smith | not that the way clojure.core does it is always best I guess |
| 15:52 | one | i see |
| 15:52 | one | i didnt write any of this code, im just trying to hack some functionality into it |
| 15:52 | one | never worked with clojure before |
| 15:52 | justin_smith | welcome! |
| 15:53 | one | the guy who wrote it claims that clojure is the best language in the world |
| 15:53 | one | :p |
| 15:53 | one | i think its excessive for an api tho |
| 15:56 | one | can i do something like |
| 15:56 | one | args :as x and then do kwargs |
| 15:56 | justin_smith | absolutely |
| 15:57 | one | and then have some logic to assign defailts to the values i x? |
| 15:57 | one | i think thats the best way |
| 15:58 | one | i guess have to count the len of args |
| 15:59 | justin_smith | ,((fn [& [a b c :as args]] (let [defaults [1 2 3] bindings (map #(or % %2) args defaults) [a b c] bindings] [a b c]) 42 43) |
| 15:59 | clojurebot | #<RuntimeException java.lang.RuntimeException: EOF while reading> |
| 15:59 | justin_smith | err |
| 16:00 | one | ah |
| 16:00 | one | nice |
| 16:00 | one | :p |
| 16:01 | one | btw, is it improper to end functions with ))))]}))]) and not use ANY indentation at all? |
| 16:01 | justin_smith | yes |
| 16:01 | justin_smith | err |
| 16:01 | one | makes it hard to read tho |
| 16:01 | justin_smith | no, not improper, that's the right way to do it, we don't do hanging delimiters |
| 16:02 | one | i see |
| 16:02 | one | its very confusing trying to read that in vim :p |
| 16:02 | ridcully | use paredit |
| 16:02 | justin_smith | there is surely a better way to do this: |
| 16:02 | justin_smith | ,(fn [& [a b c :as args]] (let [defaults [1 2 3] bindings (map #(or % %2) (concat args (repeat nil)) defaults) [a b c] bindings] bindings)) 42 43) |
| 16:02 | clojurebot | #object[sandbox$eval51$fn__53 0x45c7be7 "sandbox$eval51$fn__53@45c7be7"] |
| 16:02 | justin_smith | ,((fn [& [a b c :as args]] (let [defaults [1 2 3] bindings (map #(or % %2) (concat args (repeat nil)) defaults) [a b c] bindings] bindings)) 42 43) |
| 16:02 | clojurebot | (42 43 3) |
| 16:04 | justin_smith | one: typically we don't read the parens - we use something like paredit that makes sure the parens are good (or even just auto-indent and fixing anything that indents funky) |
| 16:05 | one | i see |
| 16:05 | one | that makes sense |
| 16:05 | justin_smith | see also rainbow-delimiters that makes non-matching ones an ugly color |
| 16:05 | ridcully | paredit made me stop worrying. cljformat cleans up after me |
| 16:05 | justin_smith | yeah, cljformat looks like a game changer |
| 16:06 | ridcully | add the vim-sexpr-something-them-name-i-forgot and you are good to go |
| 16:06 | justin_smith | yeah, vim definitely has some decent tools for working with lisp |
| 16:07 | justin_smith | I use emacs with evil mode turned on myself, but am seriously considering trying vim again since I already use most of hte keybindings |
| 16:17 | postpunkjustin | spacemacs |
| 16:19 | lxsameer | hey people, I have a json api and I need a background job and an scheduler , what do you suggest? |
| 16:20 | justin_smith | lxsameer: java.util.concurrent.ScheduledThreadPoolExecutor |
| 16:20 | justin_smith | it's not a hard api, and it's got all the right features for scheduling periodic tasks |
| 16:20 | lxsameer | justin_smith: thanks man |
| 16:21 | postpunkjustin | lxsameer: there's also overtone/at-at, which you may find more convenient |
| 16:21 | justin_smith | postpunkjustin: eh, it's a thin wrapper to what I just suggested :P |
| 16:22 | lxsameer | cool |
| 16:23 | michael_teter | something strange has happened. I haven't used emacs in a couple of weeks, and now it fails on start with one after another error from my init |
| 16:24 | michael_teter | I've been pulling out things, and by now I think there's some root problem that's causing everything to fail |
| 16:24 | michael_teter | maybe it's a hint that I should learn Cursive :/ |
| 16:24 | justin_smith | michael_teter: try deleting your .elc files - it could be that a melpa update broke some things with your older installed libs |
| 16:24 | justin_smith | or use cursive, cursive looks cool |
| 16:25 | michael_teter | it does, but it's yet another learning curve :). I will, but damnit I finally came to love Emacs. It's just that Cursive's debugger is so sexy |
| 16:25 | michael_teter | thanks, I'll try |
| 16:25 | justin_smith | postpunkjustin: perhaps I am too grumpy about the thin wrappers - it just seems like we'd all be better off doing the interop but maybe that's idealistic |
| 16:25 | postpunkjustin | eh, it's a matter of taste |
| 16:29 | justin_smith | postpunkjustin: for example, ther other day in order to do something with an explicitly provided timezone (and not just a fixed numeric offset from GMT) I had to chase the docs from clj-time to joda-time to java.util where I finally found the method I needed |
| 16:29 | postpunkjustin | yeah, stuff like that is definitely frustrating |
| 16:29 | justin_smith | wrappers! |
| 16:31 | ridcully | what they are good for? |
| 16:31 | justin_smith | but this means I'm only a few steps removed from that grouchy assembler programmer who thinks c is just a bunch of lossy abstractions that waste your time, heh |
| 16:31 | postpunkjustin | you'll get there someday, no need to rush it |
| 16:42 | amalloy | justin_smith: reminds me of https://ro-che.info/ccc/20 |
| 16:45 | justin_smith | haha |
| 17:10 | one | icant figure out how tp pass both args and kwargs |
| 17:10 | justin_smith | one: kwargs have to come after the args |
| 17:10 | ridcully | and i thought i was in #python |
| 17:10 | justin_smith | one: also, it's nice to use a hash-map with the args instead of kwargs if that's an option |
| 17:10 | one | if i do & [x y z :as args {:keys [d e f]}] |
| 17:11 | justin_smith | one your args and kwargs can't both be optional |
| 17:11 | one | is that the proper syntax? |
| 17:11 | justin_smith | no, because you can't have both optional args and kwargs |
| 17:11 | one | theres no way to force that behaviour? |
| 17:15 | WorldsEndless | I'm using CAS in my web app, which requires a return address for after the CAS handshake occurs. Anyone know a quick and easy way (maybe Ring or Compojure) to grab my app's current address, rather than hardcoding something that will break in the change from dev to production? |
| 17:16 | justin_smith | WorldsEndless: usually I use a config map for this - a mapping like {:dev "localhost" :staging "staging.example.com" :prod "example.com"} |
| 17:17 | justin_smith | and then use the env to set on of :dev / :staging / :prod |
| 17:17 | WorldsEndless | That sound smart |
| 17:17 | justin_smith | WorldsEndless: it's worked for me |
| 17:18 | justin_smith | I end up having a bunch of maps like that |
| 17:18 | WorldsEndless | out of curiosity, do you actually in the env do `export site=:dev' or does the :key need to be inserted else-ways? |
| 17:18 | justin_smith | for db ports / db hosts, api accounts to connect to, etc. |
| 17:19 | WorldsEndless | Yeah, I'm catching on to this 12-step thing. That makes sense |
| 17:19 | justin_smith | WorldsEndless: I put it in the java startup "SITE=dev java -cp my-uber.jar clojure.main my-main-class" |
| 17:19 | postpunkjustin | I think the 12-step thing is slightly different... |
| 17:19 | postpunkjustin | but hey, maybe not |
| 17:20 | justin_smith | postpunkjustin: it probably is, I am not doing 12-step to the letter |
| 17:20 | WorldsEndless | postpunkjustin: One of the emphasis I noticed (having watched the YouTube video, I'm now a pro) is taking care of your env. vars |
| 17:20 | postpunkjustin | I mean, do what works and take it one day at a time I guess. |
| 17:21 | justin_smith | postpunkjustin: so the 12 step way would be to have an environment config file that is sourced by my shell instead of putting it on the command line, right? |
| 17:21 | WorldsEndless | justin_smith: that's what I understood |
| 17:21 | justin_smith | err, 12 factor, oops |
| 17:21 | WorldsEndless | lol |
| 17:21 | WorldsEndless | I just did a double-take on that |
| 17:22 | justin_smith | I'm justin_smith, and I do dev ops. It's been 3 days since the last deploy disaster. |
| 17:22 | justin_smith | haha |
| 17:22 | WorldsEndless | lol |
| 17:22 | WorldsEndless | My first LOL with my current office neighbors... |
| 17:23 | WorldsEndless | In the 12-factor paradigm, Docker's handling of containers (with massive env setups) makes more sense |
| 17:23 | ridcully | i am disappointed. you seemed like the noops guy |
| 17:24 | justin_smith | heh |
| 17:24 | justin_smith | ridcully: I am actually not the main devops guy at my company, but that just fit the convo flow here... |
| 17:25 | ridcully | gotta do |
| 17:25 | justin_smith | I'm mainly the guy that talks about clojure on irc while occasionally implementing a feature or unit test for the product |
| 17:25 | ridcully | same here... if ya don't do it, it won't fix itself |
| 17:28 | ridcully | what are those? pragmaticops? fixops? |
| 17:28 | ridcully | navysealops? |
| 17:49 | nanuko | is there any way to repl into a clojure standalone jar as it’s executing? |
| 17:51 | justin_smith | nanuko: you can explicitly run a repl from your -main via nrepl if you add it as a dep, or you can use "java -cp your-uber.jar" to start up the process, and manually start -main in a separate thread |
| 17:51 | justin_smith | probably in screen or tmux or something for it to be really useful |
| 17:52 | nanuko | ah, that makes sense. but that wouldn’t work for something like heroku, correct? |
| 17:53 | justin_smith | yeah, on heroku nrepl is likely easier (then you can ssh tunnel to the port, and use lein repl :connect locally) |
| 17:53 | justin_smith | you can still ssh into the heroku machine once it is up, right? |
| 17:58 | nanuko | yup |
| 17:59 | nanuko | you would still have to call something like this (defonce server (start-server :port 7888)) in your app |
| 17:59 | nanuko | i think |
| 18:02 | fsjhfkjdhf | hey justin_smith you there? got another question :D |
| 18:03 | fsjhfkjdhf | or for anyone really: i'm wondering why this is just returning a function without any output: (defn myfunc [xs] (keep-indexed (fn [idx v] (if (= (dec v) (nth xs (max 0 (dec idx)))) v)))) |
| 18:04 | fsjhfkjdhf | i'm trying to get a list with only elements that are one larger than the one before them |
| 18:06 | amalloy | you never use xs |
| 18:08 | one | SUCESS |
| 18:08 | fsjhfkjdhf | amalloy: yeah i do? right after nth |
| 18:08 | amalloy | (defn myfunc [xs] (keep-indexed (fn ...))) |
| 18:09 | fsjhfkjdhf | ah |
| 18:09 | fsjhfkjdhf | ok changed that and it's still not giving me anything |
| 18:09 | fsjhfkjdhf | (defn myfunc [xs] (keep-indexed (fn [idx v] (if (= (dec v) (nth xs (max 0 (dec idx)))) v)) xs)) |
| 18:09 | amalloy | ,(defn myfunc [xs] (keep-indexed (fn [idx v] (if (= (dec v) (nth xs (max 0 (dec idx)))) v)) xs)) |
| 18:09 | clojurebot | #'sandbox/myfunc |
| 18:10 | amalloy | ,(myfunc [1 2 4 5]) |
| 18:10 | clojurebot | (2 5) |
| 18:10 | amalloy | LGTM |
| 18:10 | fsjhfkjdhf | ohhhh my repl was broken |
| 18:32 | WorldsEndless | Anyone bumpted into SLF4J "multiple binding" errors before? Apparently two of my dependencies use conflicting versions of SLF4j |
| 18:32 | WorldsEndless | But I'm not sure which ones they are.. |
| 18:33 | justin_smith | WorldsEndless: SLF4j defines an interface, and iirc this issue is that you have two different libs that are available that implement the interface - usually this means it just ends up picking one and warning you that two both were available |
| 18:34 | justin_smith | "The Simple Logging Facade for Java (SLF4J) serves as a simple facade or abstraction for various logging frameworks (e.g. java.util.logging, logback, log4j) allowing the end user to plug in the desired logging framework at deployment time." |
| 18:35 | justin_smith | http://www.slf4j.org/ - so the conflict isn't two versions of one lib, it's two libs that both want to provide a dep for slf4j, and slf4j feels that it is underconfigured |
| 18:35 | WorldsEndless | Yeah, it tells me the repos are ch.qos.logback.logback-classic, and org.slf4j, but neither of those are really ringing a bell |
| 18:35 | justin_smith | WorldsEndless: "lein deps :tree" will show you who pulls each of those in, then you can exclude one |
| 18:35 | WorldsEndless | Ah! That's the command I needed. Thanks. |
| 18:36 | justin_smith | slf4j itself will not provide a logger, iirc - it needs one of the other libs |
| 18:38 | WorldsEndless | Whoa. It has lots of "consider these exclusions" lines |
| 18:38 | WorldsEndless | far more than just slf4j |
| 18:38 | WorldsEndless | like, |
| 18:38 | WorldsEndless | Consider using these exclusions: |
| 18:38 | WorldsEndless | [lein-figwheel "0.5.0-2" :exclusions [org.clojure/clojure]] |
| 18:38 | WorldsEndless | |
| 18:38 | WorldsEndless | which seems strange to me |
| 18:41 | WorldsEndless | He rowed away... |
| 18:44 | ridcully | no he did'nt |
| 18:44 | WorldsEndless | Strange that things that bring in newer versions get overridden by things using older versions |
| 18:44 | WorldsEndless | Or maybe that's by design. |
| 18:54 | fsjhfkjdhf | anyone know why this isn't working? (defn subsequences [xs] (reduce (fn [acc v] (if (= (dec v) (last (last acc))) (conj (last acc) v) (conj (last acc) [v]))) [] xs)) |
| 18:54 | fsjhfkjdhf | trying to get a vector of subsequence vectors.. |
| 18:54 | fsjhfkjdhf | keep getting error: java.lang.IllegalArgumentException: Don't know how to create ISeq from: java.lang.Long |
| 18:59 | justin_smith | fsjhfkjdhf: why (last (last acc)) ? |
| 18:59 | fsjhfkjdhf | hi justin! |
| 18:59 | fsjhfkjdhf | uhmmm let's see |
| 18:59 | justin_smith | for that to work, you should use a different init |
| 18:59 | justin_smith | (I think) |
| 19:00 | fsjhfkjdhf | well i want to add it to the embedded vector if it's a part of the same sequence |
| 19:00 | fsjhfkjdhf | otherwise i want to create a new vector |
| 19:00 | fsjhfkjdhf | the first test should always fail |
| 19:00 | fsjhfkjdhf | because it will be comparing a number to an empty vector |
| 19:00 | fsjhfkjdhf | and that will create a new vector |
| 19:01 | fsjhfkjdhf | oh wait |
| 19:01 | fsjhfkjdhf | i think i see a problem |
| 19:01 | justin_smith | fsjhfkjdhf: the error is (conj (last acc) v) |
| 19:02 | fsjhfkjdhf | really |
| 19:02 | fsjhfkjdhf | hmm |
| 19:02 | justin_smith | replace that with (conj (pop acc) (conj (last acc) v)) |
| 19:02 | justin_smith | otherwise you lose most of the acc - and it has the wrong shape next time through |
| 19:03 | justin_smith | and then you get the error next time thorugh - it is a vector of numbers instead of a vector of vector of numbers |
| 19:03 | justin_smith | remember that what you return from the fn is the entirety of acc next time |
| 19:03 | fsjhfkjdhf | oh right.. |
| 19:03 | fsjhfkjdhf | hmm this is harder than i initially hoped for lol |
| 19:03 | justin_smith | so really both your branches of that if need to use pop acc ass above |
| 19:04 | justin_smith | also, you can use peek instead of last for style / efficiency points |
| 19:05 | slester | if I want to take certain letters out of (def abcs (map char (range (int \a) (inc (int \z))))), how do I do that exactly? :( |
| 19:05 | justin_smith | (if (= (dec v) (peek (peek acc))) (conj (pop acc) (conj (peek acc) v)) (conj acc [v])) |
| 19:05 | slester | like I want to remove '((int \c) (int \d)) |
| 19:06 | justin_smith | (remove #{\c \d} abcs) |
| 19:06 | justin_smith | ,(remove #{\c \d} map char (range (int \a) (inc (int \z))))) |
| 19:07 | clojurebot | #error {\n :cause "Wrong number of args (4) passed to: core/remove"\n :via\n [{:type clojure.lang.ArityException\n :message "Wrong number of args (4) passed to: core/remove"\n :at [clojure.lang.AFn throwArity "AFn.java" 429]}]\n :trace\n [[clojure.lang.AFn throwArity "AFn.java" 429]\n [clojure.lang.AFn invoke "AFn.java" 44]\n [sandbox$eval25 invokeStatic "NO_SOURCE_FILE" 0]\n [sandbox$eval2... |
| 19:07 | justin_smith | oops |
| 19:07 | justin_smith | ,(remove #{\c \d} (map char (range (int \a) (inc (int \z))))) |
| 19:07 | clojurebot | (\a \b \e \f \g ...) |
| 19:07 | slester | what is #{} doing there exactly? |
| 19:08 | justin_smith | ,(map #{1 2} (range)) |
| 19:08 | clojurebot | (nil 1 2 nil nil ...) |
| 19:08 | justin_smith | does that help? |
| 19:08 | justin_smith | ,(#{:foo :bar} :foo) |
| 19:08 | clojurebot | :foo |
| 19:08 | justin_smith | ,(#{:foo :bar} :baz) |
| 19:08 | clojurebot | nil |
| 19:08 | slester | that's really hard to google for, what's it called? |
| 19:09 | justin_smith | ,(type #{}) |
| 19:09 | clojurebot | clojure.lang.PersistentHashSet |
| 19:09 | slester | not really, but I'm not very smart |
| 19:09 | slester | thanks |
| 19:09 | justin_smith | slester: when you use a set as a function, it returns the arg, if the arg is in the set |
| 19:09 | justin_smith | othwerwise it returns a default, and the default default is nil |
| 19:10 | slester | oh I see, so remove applies the pred to the list, and they all return nil unless they're in the set |
| 19:10 | justin_smith | right |
| 19:10 | justin_smith | and if the f for remove returns nil, the item is not removed |
| 19:10 | justin_smith | basically, a set can be used as a way to test if a value belongs to some set of values you are interested in |
| 19:12 | slester | justin_smith: thanks, you're a lifesaver (or at least a time- and brain-saver) |
| 19:13 | justin_smith | heh, I try |
| 19:13 | slester | always nice to have nice helpful gurus about, makes me much more likely to keep pounding my head against clojure until it sticks |
| 19:14 | justin_smith | man, if I was a guru I could talk people into giving me their life savings, or I could levitate maybe... something |
| 19:14 | slester | haha |
| 19:14 | slester | isn't creating something out of nothing guru-esque? |
| 19:15 | slester | programming hurray |
| 19:17 | justin_smith | fair |
| 19:49 | didibus | I've got a function that takes a vararg and some other args. How can I call tha function, give it the normal arg, and pass a map to it as the vararg? |
| 19:49 | didibus | I know apply would work if it only takes a vararg |
| 19:50 | didibus | oh, nevermind, apply does work in this case too |
| 20:04 | alive876 | hi, could any one tell me when i run lein on a project it comes back with xx is not a task ? thanks in advance! |
| 20:21 | tolstoy | alive876: The second param to lein is a task. "lein run" "lein test" and so on. If you specify a task that doesn't exist, you get that message. |
| 20:24 | alive876 | ok thanks |
| 21:24 | irctc | Hi everyone. :) |
| 21:25 | irctc | Is there a way to select only parts of XML between two nodes so that I could parse just that part from an XML document instead of the entire thing? |
| 21:27 | irctc | For example I'd jiust like to parse the stuff between the <bar></bar> nodes but my document looks like <foo><boo><bar><element></element></bar></boo></foo> |
| 21:29 | tolstoy | Seems like you could 1) do some regex on the string, or 2) just parse it, pull out the node you want and throw the rest away. |
| 21:30 | tolstoy | clojure.xml/parse turns XML to clojure data. From there, you could find the right place. |
| 21:30 | irctc | I am already doing it the second way. |
| 21:31 | irctc | I don't know regex and am a bit scared of working with it. It just looks weird lol |
| 21:31 | tolstoy | Are you worried about the size of the XML or something? |
| 21:31 | irctc | Well it's the performance hit that my app takes and I'd just like to process a smaller part of it. |
| 21:32 | irctc | From performing functions at 1msec it goes all the way up to about a 1000 msecs and I'd like to lower that as much as possible. |
| 21:33 | tolstoy | This claims to be lazy: https://github.com/clojure/data.xml. Perhaps that fits? |
| 21:33 | irctc | That's when it has to parse the xml file. Because I don't need the entire file parsed I thought I'd just cut it down from the get go. |
| 21:34 | tolstoy | Maybe the "lazy" version doesn't parse the whole thing, so you only have to worry about every in front of "<bar/>". |
| 21:35 | irctc | And clojure.xml isn't lazy? |
| 21:35 | tolstoy | Hm. Read in the string, split on "<", then (drop-while not= "<bar", then take-while (not= "</bar") and join the string up again and parse? |
| 21:36 | tolstoy | clojure.xml/parse doesn't mention the word lazy, so I assume not. |
| 21:36 | irctc | Hmmmm, that might actually work. I'll test to see how much time it takes to process the file before I parse it. |
| 21:37 | tolstoy | Anyway, I think the reason data.xml exists is to provide that lazyiness. |
| 21:37 | tolstoy | Yeah. How fast is string/split? Etc. |
| 21:38 | irctc | Thanks tolstoy. Btw, Tolstoy is one of my favorite authors. Don't know if you chose that nickname because of him, it just reminded me of him. :) |
| 21:38 | tolstoy | In Emacs, I used to load up a message XML file, then string-replace >< with >\n< and then select-all, then hit tab. Cleans it right up! |
| 21:39 | irctc | That's a neat solution and I thought of doing that but the elements before the elements that I actually need vary in length so I can't rely on that. |
| 21:39 | tolstoy | My fave is Chekhov, actually. |
| 21:41 | tolstoy | Is the file already broken into lines? |
| 21:41 | irctc | I don't know what that means. |
| 21:42 | tolstoy | Are there carriage returns in the XML file already, or is it just one big long string. |
| 21:42 | tolstoy | I know you've read it in as a big string, but maybe there are "\n" in it. |
| 21:42 | tolstoy | Split on those, then compare strings. |
| 21:43 | irctc | Nah, just a big long string. |
| 21:44 | tolstoy | How much do you know about XML processing? Like, DOM vs SAX and so on? |
| 21:45 | irctc | Oh, not that much. |
| 21:45 | irctc | Did some basic DOM navigation but that's about it. |
| 21:45 | tolstoy | With DOM, you load the whole thing in, then you can do Xpath with it. |
| 21:46 | tolstoy | With SAX, you register a handler which is notified of each node as you go along. |
| 21:46 | irctc | I'm actually thinking of doing this to replace multiple strings with /n: http://stackoverflow.com/questions/9568050/in-clojure-how-to-write-a-function-that-applies-several-string-replacements |
| 21:47 | tolstoy | So, you could just "if the node doesn't equal bar, don't do anything", but I don't think you can say, "Here's bar, now return the entire sub-tree." |
| 21:48 | tolstoy | Hm. You could (s/split xml #"<bar|</bar") maybe. |
| 21:49 | irctc | Let me try that. That sounds nice. |
| 21:50 | tolstoy | ,(clojure.string/split "<foo><bar><baz>hello</baz></bar></foo>" #"<baz>|</baz>") |
| 21:50 | clojurebot | ["<foo><bar>" "hello" "</bar></foo>"] |
| 21:51 | tolstoy | ,(str "<baz>" (second (clojure.string/split "<foo><bar><baz>hello</baz></bar></foo>" #"<baz>|</baz>")) "</baz>") |
| 21:51 | clojurebot | "<baz>hello</baz>" |
| 21:52 | irctc | How would I select just the "hello" from that vector if I don't know where it's going to be because the nesting hierarchy varies? |
| 21:52 | tolstoy | The assuming is that there's just one <baz> element in the whole doc. |
| 21:53 | tolstoy | s/assuming/assumption/ |
| 21:53 | irctc | (second (clojure.string/split "<foo><bar><baz>hello</baz></bar></foo>" #"<bar>|</bar>")) |
| 21:53 | irctc | ,(second (clojure.string/split "<foo><bar><baz>hello</baz></bar></foo>" #"<bar>|</bar>")) |
| 21:53 | clojurebot | "<baz>hello</baz>" |
| 21:54 | irctc | Sometimes there are multiple. |
| 21:54 | tolstoy | I think "split" takes a max number of values to return. |
| 21:56 | tolstoy | So, some sort of loop/recur where you (loop [xml xml] (let [[_ bar rest] (split xml #"<bar>|</bar>" 3) (process bar) (recur rest)) ) or something like that. |
| 21:56 | irctc | ,(second (clojure.string/split "<foo><bar><baz>hello</baz><baz>hello</baz><baz>hello</baz></bar></foo>" #"<bar>|</bar>" 2)) |
| 21:56 | clojurebot | "<baz>hello</baz><baz>hello</baz><baz>hello</baz></bar></foo>" |
| 21:56 | irctc | ,(clojure.string/split "<foo><bar><baz>hello</baz><baz>hello</baz><baz>hello</baz></bar></foo>" #"<bar>|</bar>" 2) |
| 21:56 | clojurebot | ["<foo>" "<baz>hello</baz><baz>hello</baz><baz>hello</baz></bar></foo>"] |
| 21:57 | irctc | Ok, so it stops splitting at the limit. |
| 21:57 | irctc | But returns the last element unprocessed. |
| 21:58 | tolstoy | Right. Then you take that unprocess element, and try again. Keep going until there's none left. |
| 21:58 | tolstoy | You could do it in a recursive function that just gathers up the "good" parts and returns them. |
| 22:02 | tolstoy | irctc: Something like this? https://gist.github.com/zentrope/9d09c91deab0351421e5 (untested). |
| 22:07 | tolstoy | Oy, that's bad code. |
| 22:09 | tolstoy | Okay, this works: https://gist.github.com/zentrope/9d09c91deab0351421e5 |
| 22:10 | tolstoy | Could make a version that uses lazy-seq, but I'd have to remember how. ;) |
| 22:11 | irctc | That's a cool solution. :) Thanks! :) |
| 22:13 | justin_smith | irctc: see also clj-tagsoup if you know the tag that will contain your content, but not the structure |
| 22:13 | justin_smith | it has a lazy version too |
| 22:13 | justin_smith | https://github.com/nathell/clj-tagsoup |
| 22:17 | irctc | Thanks justin_smith. :) |
| 22:19 | noobie_ | any idea why this wouldn't work? (read-stdin) is defined as (defn read-stdin [] (line-seq (java.io.BufferedReader. *in*))) |
| 22:20 | noobie_ | http://sprunge.us/JLGK |
| 22:20 | noobie_ | something about not being able to use nth |
| 22:21 | tolstoy | irctc: Well, added a lazy-seq version. I think. |
| 22:21 | justin_smith | noobie_: looks like it works to me https://www.refheap.com/112613 |
| 22:22 | justin_smith | noobie_: perhaps you are trying to use it in the repl, and the repl already wants to own *in* ? |
| 22:22 | justin_smith | or perhaps nothing is consuming the lazy-seq |
| 22:24 | justin_smith | noobie_: common/read-stdin is a function, not a function call |
| 22:24 | irctc | Thanks tolstoy. :) |
| 22:24 | justin_smith | noobie_: sorry about my above, I had not seen your paste |
| 22:24 | justin_smith | noobie_: if you replace common/read-stdin (a function) with (common/read-stdin) (a call to that function) it should print your first line |
| 22:24 | tolstoy | irctc: Heh. The addition to that post actually works. If you add printlns and then (take 1 ...) from each method, the get-bars function parses the whole thing before returning the first element, while lazy-seq version only does the first. Ugly, but it works-ish. |
| 22:25 | noobie_ | justin_smith: ahh, yes |
| 22:25 | noobie_ | justin_smith: do i require doseq instead of let? |
| 22:25 | noobie_ | let seems to act weird with a line-seq |
| 22:25 | tolstoy | irctc: I guess that's useful if you're worried about memory. |
| 22:25 | justin_smith | noobie_: if you replace if-not with when-not, it would even recur and consume more than one non-nil line |
| 22:25 | justin_smith | noobie_: it's not let that is misbehaving I bet |
| 22:26 | justin_smith | noobie_: what do you expect to happen - do you expect more than one line to be printed? |
| 22:26 | noobie_ | i expect them to be print as i type them |
| 22:26 | noobie_ | right after i hit enter |
| 22:26 | justin_smith | noobie_: your if-not ensures that it only recurs if the line is nil |
| 22:26 | justin_smith | you want it to recur for every line until one of them is nil |
| 22:27 | justin_smith | noobie_: maybe you mean when-not rather than if-not |
| 22:27 | noobie_ | hmm yeah |
| 22:27 | justin_smith | noobie_: the reason I used doseq is I had not seen your code yet, and doseq is the normal way to perform some side effect for each item in a sequence |
| 22:27 | justin_smith | noobie_: you can do the same thing with loop, but doseq makes it simpler |
| 22:28 | justin_smith | err, s/loop/recur means the same thing in this case effectively |
| 22:28 | noobie_ | doesn't do seq force an evaluation? |
| 22:28 | justin_smith | noobie_: yes, you won't get any result unless you force the lazy input |
| 22:28 | tolstoy | One more fix! ;) |
| 22:28 | justin_smith | recur is strict to |
| 22:29 | justin_smith | noobie_: doseq performs some action for every item in an input, perhaps you are thinking of doall or dorun which are meant for forcing laziness |
| 22:42 | Trioxin | I'm going to attempt to make an applet out of clojure and load it into nwjs where my jar will run and interact with the javascript and clojurescript on the page. If I'm not successful, what would be the second best way to pipe data back and forth between the DOM in nwjs (Basically chromium with node running and DOM/node interop). Let's say in the most extreme case this data is a video stream. A local socket? Quantum entanglement? |
| 22:44 | Trioxin | pipe via command line in node even? need fastest route |
| 22:45 | justin_smith | file mapped to shm |
| 22:45 | justin_smith | maybe? |
| 22:45 | Trioxin | what's shm? |
| 22:46 | justin_smith | shared memory - memory that two programs are both allowed to access |
| 22:46 | Trioxin | oh |
| 22:46 | justin_smith | Trioxin: http://www.boost.org/doc/libs/1_38_0/doc/html/interprocess/sharedmemorybetweenprocesses.html |
| 22:46 | justin_smith | typically the least safe possible way to share data between programs, also the fastest |
| 22:47 | justin_smith | "Shared memory is the fastest interprocess communication mechanism. The operating system maps a memory segment in the address space of several processes, so that several processes can read and write in that memory segment without calling operating system functions. However, we need some kind of synchronization between processes that read and write shared memory." |
| 22:47 | amalloy | i bet we could come up with less safe ways |
| 22:47 | amalloy | morse code transmitted via the medium of nuclear explosions |
| 22:47 | Trioxin | lol |
| 22:47 | justin_smith | amalloy: heh, how about less safe, and you also have valid reasons to consider using it? |
| 22:50 | Trioxin | i bet shm would be even better than applet/JS |
| 22:50 | Trioxin | so jar/node shm |
| 22:51 | Trioxin | since in nwjs I can run node code in the dom anyway |
| 22:51 | justin_smith | Trioxin: in practice you don't see this sort of thing because it is way easy to crash programs if you do it wrong |
| 22:52 | justin_smith | I was just literally answering the "what's the fastest way to communicate between two programs" question |
| 22:52 | Trioxin | hm |
| 22:53 | Trioxin | piping is probably crap |
| 22:53 | Trioxin | or is that done at the kernel level? |
| 22:54 | justin_smith | it is, and that makes it slow because of the switches to kernel mode (syscalls are rarely cheap from userland) |
| 22:55 | justin_smith | but maybe that's just unavoidable considering we are talking about two different programs communicating here |
| 22:55 | Trioxin | so then we have local sockets or if I can get my clj in an applet |
| 22:56 | Trioxin | there are some oooold examples of clojure applets that java won't run under normal security but i think in the nwjs environment it would run it |
| 22:56 | justin_smith | Trioxin: almost always - make something that works first, then figure out what's too slow and see what you can speed up out of that. Optimizing before your code works rarely turns out well. |
| 22:56 | Trioxin | justin_smith, there's that but then also the fact that there's a big difference between the code for shm and sockets |
| 22:57 | Trioxin | sockets don't sound too bad actually |
| 22:58 | Trioxin | easy to handle |
| 22:58 | justin_smith | not a huge difference - your "read" becomes "wait until value is available, then access", your "write" becomes "wait until read access is available, then store" |
| 22:58 | justin_smith | err, write access, of course |
| 22:59 | jabb | feels like i'm getting stdin cut off |
| 23:00 | justin_smith | jabb: what's the symptom? |
| 23:02 | Trioxin | eh. of course no webrtc lib for clojure up to date I can find |
| 23:02 | Trioxin | maybe will be my first time trying to wrap my own java thing |
| 23:02 | justin_smith | Trioxin: interop is easy, and people don't take advantage of it as much as they should |
| 23:03 | Trioxin | oh I will |
| 23:03 | Trioxin | there's still some untapped market share in the p2p space to be had |
| 23:04 | jabb | justin_smith: http://ideone.com/BZjo30 |
| 23:04 | justin_smith | an easy and cool thing would be to port this to clojure, for use in unit-tests with functions that take strings https://github.com/minimaxir/big-list-of-naughty-strings/blob/master/naughtystrings/internal/resource.go#L530 |
| 23:06 | justin_smith | jabb: stdout is buffered, in order to make it print you must either use (flush) or something that calls (flush) like (println) - println is not flushing because the input has not ended. |
| 23:06 | justin_smith | line-seq doesn't end until the input is closed |
| 23:07 | jabb | should close on eof, yeah? |
| 23:07 | jabb | adding flush didn't help |
| 23:07 | justin_smith | in this case, you could change "let" into "doseq" - not because doseq can replace let, but in this case it would incidentally work, and it would print each line of input on a line |
| 23:07 | jabb | hmm |
| 23:07 | justin_smith | jabb: where did you add flush? |
| 23:07 | jabb | after println |
| 23:08 | justin_smith | println doesn't return |
| 23:08 | justin_smith | because stdin hasn't closed |
| 23:08 | Trioxin | isn't there another flush method... ob something or other (This was from a different language) |
| 23:08 | Trioxin | that also had flush |
| 23:08 | justin_smith | jabb: println itself calls flush, but that only helps if it actually finishes |
| 23:09 | justin_smith | you are asking it to print a value, then it's hanging trying to read more of that value... |
| 23:09 | justin_smith | jabb: like I said, try just changing let to doseq and see what happens |
| 23:09 | jabb | ahh |
| 23:09 | jabb | i'm sure that'll work, i'm just trying to use a series of reduces and stuff on input |
| 23:10 | jabb | so doseq wouldn't work for that |
| 23:10 | justin_smith | (reduce println input) |
| 23:10 | justin_smith | that will also work |
| 23:10 | justin_smith | later you can replace println with a function that does other stuff too |
| 23:11 | jabb | i tested this with "lein tampoline run > out" and "cat - > out2" and compared the two files |
| 23:11 | jabb | one was larger than the other by 3 characters |
| 23:11 | jabb | same input |
| 23:11 | jabb | ctrl-d on stdin to force a write |
| 23:11 | justin_smith | I bet out had at least one extra newline |
| 23:12 | jabb | yeah, one had a newline, the other had a character missing from the front and back |
| 23:12 | jabb | here, sec, i'll have you test |
| 23:12 | Trioxin | what if... I take all the clojure snippets on the net and feed them to a genetic algorithm for the purpose of meeting a fitness of increasing it's awareness, capabilities, and inferred data via convolutional ANNs? |
| 23:13 | Trioxin | WILL WE DIE |
| 23:13 | TEttinger | Trioxin: you do know what most of my clojure snippets on the net do, right? |
| 23:13 | Trioxin | what? |
| 23:13 | clojurebot | what is bbloom bitching about OOP |
| 23:13 | TEttinger | ,(let[a #(apply str(flatten %))r repeatedly p partition N rand-nth n #(a(N(concat(repeat %"")(mapcat p[1 2 3]%&))))v #(n 0"aioeu""iaai")w(fn[](let[b(n 6"!.""""...")s[(n 0"STKNYPKLG""GlThShNyFt""ZvrCth")(r(N[1 2])#(do[(v)(n 9(map str"'-"(r 2 v)))(n 0(concat"lpstnkgx"[(N["h""gl""gr""nd"])(v)])"rlthggghtsltrkkhshng")]))]][b(if(seq b)[" "s][(n 3",")" "(.(a s)toLowerCase)])]))](re-find #"[A-Z].+"(a[(r 500 w)"."]))) |
| 23:13 | clojurebot | "Glax kiarl gliapa-ial! Gliaxult... Pekogg... Piat. Te-okhogg, yaie, zvraxilt, yailt. Thukh pigg. Nyo'ol peggaigr negg zvriat, yiaghai'iarl kiaghex, kuth. Ftogh, fton... Zvrukhigh yash. Cthuuiap kugip nixiak tipaigg, lulogh glih gig... Poggigg. Gakegg kot, kuts kakh shakukh, thaikup cthot. Glai'ukot, nosiaai! Poia, kaitsang. Nugh. Kirl ko-op nyairl! Shos. Pe-ak, ctharliagg nuxiagr zvrix, zvruo! Ke... |
| 23:14 | jabb | justin_smith: source: http://sprunge.us/WcfH input: http://sprunge.us/OMQF |
| 23:14 | Trioxin | skynet is upon us |
| 23:14 | TEttinger | Ia! Ia! |
| 23:15 | jabb | sounds lovecraftian |
| 23:15 | jabb | TEttinger: know me? |
| 23:15 | TEttinger | hm... let me check... |
| 23:16 | Trioxin | jabb is the bottom from meatspin |
| 23:16 | justin_smith | jabb: you are using line-seq on a one line file |
| 23:16 | jabb | justin_smith: true, but could be more than one |
| 23:16 | jabb | who knows? :D |
| 23:18 | fsjhfkjdhf | hey this is a bit of a stupid question but how do i insert a list into a list? like let's say i have this list ['(1 2) '(3 4)] |
| 23:18 | fsjhfkjdhf | and i do (take 2 '(5 6 7 8)) |
| 23:19 | jabb | ,(concat '(1 2) '(3 4)) |
| 23:19 | clojurebot | (1 2 3 4) |
| 23:19 | fsjhfkjdhf | that's not quite it |
| 23:19 | fsjhfkjdhf | it flattens it |
| 23:19 | fsjhfkjdhf | i want it to be ['(1 2) '(3 4) '(5 6)] |
| 23:19 | justin_smith | ,(conj '[(1 2) (3 4)] (take 2 '(5 6 7 8))) |
| 23:19 | clojurebot | [(1 2) (3 4) (5 6)] |
| 23:19 | fsjhfkjdhf | that's what i thought too but it wasnt working.. |
| 23:20 | fsjhfkjdhf | hm ill try again |
| 23:20 | jabb | justin_smith: try my snippet? :) |
| 23:20 | justin_smith | fsjhfkjdhf: remember that conj does not change the input |
| 23:20 | justin_smith | jabb: yeah, playing with it right now |
| 23:20 | fsjhfkjdhf | yeah still doesnt seem to be working hmm |
| 23:20 | jabb | seeing the same discrepency? missing two characters from both ends? |
| 23:21 | fsjhfkjdhf | (def sample [0 1 2 3 4 5 6 7 ]) |
| 23:21 | Trioxin | thou shalt copy and paste into thy repl |
| 23:21 | fsjhfkjdhf | (conj (take 2 (drop 2 sample)) ['(1 2) '(3 4)]) |
| 23:21 | fsjhfkjdhf | is giving me ([(1 2) (3 4)] 2 3) |
| 23:21 | justin_smith | fsjhfkjdhf: your args are in the wrong order |
| 23:22 | fsjhfkjdhf | omg lol |
| 23:22 | fsjhfkjdhf | thank you |
| 23:24 | justin_smith | jabb: the difference is that the lines coming from line-seq are wrapped in parens |
| 23:24 | jhn | why do core.async/map and core.async.reduce operate on different arguments, unlike regular m/r? |
| 23:24 | justin_smith | jabb: this would be easier to see if your input file had more lines, and they were not composed of parens |
| 23:24 | jhn | as in: https://clojure.github.io/core.async/#clojure.core.async/map |
| 23:24 | jhn | vs. https://clojure.github.io/core.async/#clojure.core.async/reduce |
| 23:25 | jhn | map operates on a collection of channels. |
| 23:25 | jhn | but reduce operates on the items of a single channel. |
| 23:25 | jabb | justin_smith: should that matter? |
| 23:26 | jabb | just two characters |
| 23:26 | justin_smith | jabb: you asked it to print a collection, when a collection is printed the parens are printed with it |
| 23:26 | jabb | unless lisp is eating them? |
| 23:26 | justin_smith | lisp is not eating anything |
| 23:26 | justin_smith | you asked it to print a list, the parens are how lists are printed |
| 23:26 | jabb | ahh |
| 23:26 | justin_smith | so it added parens |
| 23:26 | jabb | hmm |
| 23:26 | jabb | i seee |
| 23:28 | justin_smith | jabb: this version will print the input (reduce #(println %2) nil (line-seq (java.io.BufferedReader. *in*))) |
| 23:28 | justin_smith | start with that, verify it replicates your input, then put a more interesting function in there instead of #(println %2) |
| 23:30 | justin_smith | jabb: on each call, the fn will get "previous return value" as its first arg, and "next line" as the second |
| 23:37 | Trioxin | tettinger, you have site with your codes? |
| 23:38 | TEttinger | not really, that one was written mostly in an IRC window :) |
| 23:38 | TEttinger | oh! |
| 23:38 | Trioxin | it's okay I don't have one either but I shall make one |
| 23:39 | TEttinger | this is roughly the same sort of output but much clearer input http://ideone.com/L0eHc6 |
| 23:39 | Trioxin | first i'll fill it with all my lame C# and PHP/MySQL |
| 23:39 | Trioxin | then... |
| 23:40 | Trioxin | you know |
| 23:40 | Trioxin | I've done craziness in PHP |
| 23:40 | Trioxin | pushing it to its limits because I learned it first |
| 23:41 | TEttinger | a friend used this for his game, actually http://ideone.com/zwnFAL |
| 23:41 | TEttinger | (the output) |
| 23:41 | TEttinger | Planetary System Cabal (hm, what could possibly go wrong...) |
| 23:44 | TEttinger | It's kinda strange how very very well-suited clojure is as a language for text processing. it has slow startup at the command line, which is a mark against, but just about every program involving regexes and more importantly sequences of matches is really just so easy to write. |
| 23:44 | TEttinger | (I just wrote some java to do some text handling, it's ugggghhhhh) |
| 23:44 | justin_smith | TEttinger: if you just load up clojure.jar with java, you can get load times ~ 1 second |
| 23:45 | TEttinger | is it lein that slows it down? |
| 23:45 | justin_smith | TEttinger: lein and nrepl |
| 23:45 | justin_smith | both are pretty slow to start up |
| 23:45 | TEttinger | interesting |
| 23:45 | TEttinger | how about boot> |
| 23:45 | TEttinger | ? |
| 23:46 | justin_smith | it starts faster, but if you don't need to manage classpath (either you can set it up yourself or only need clojure) java running clojure.jar can't be beat :) |
| 23:46 | TEttinger | nice. |
| 23:46 | TEttinger | I didn't expect that |
| 23:47 | justin_smith | TEttinger: try this time java -jar ~/.m2/repository/org/clojure/clojure/1.7.0/clojure-1.7.0.jar -e '(println "hello world!")' |
| 23:47 | justin_smith | should be closer to 1 second than two |
| 23:48 | TEttinger | hm. I wonder if there's some sort of subset of lein possible that can read a lein project.clj (or some easy to parse version generated from one by a lein plugin) but doesn't try to download deps or anything |
| 23:48 | justin_smith | I mean that's still slow - but it's doable |
| 23:49 | justin_smith | TEttinger: lein cp > classpath; java -cp $(cat classpath) ... |
| 23:49 | justin_smith | you only need to do the lein cp part once each time you change your deps :) |
| 23:49 | TEttinger | good ol' windows |
| 23:49 | justin_smith | ah! |
| 23:49 | TEttinger | I can do > |
| 23:49 | justin_smith | but you can still put the output of lein cp in a file |
| 23:49 | TEttinger | not sure how I'd do $ |
| 23:49 | justin_smith | but can you get that into a command line,,, |
| 23:49 | justin_smith | right, right |
| 23:50 | justin_smith | edit runclojure.bat |
| 23:50 | justin_smith | haha |
| 23:50 | TEttinger | there's powershell... |
| 23:50 | justin_smith | anyway, I'm sure there's a simple way to do it |
| 23:50 | justin_smith | just put the output of lein cp into the shell script |
| 23:50 | justin_smith | and if the shell script breaks, you can go run lein cp again |
| 23:50 | TEttinger | ha |
| 23:52 | justin_smith | TEttinger: there are various options that people don't consider because they assume java is the thing that is making startup of clojure slow |
| 23:59 | oracle | how to convert [1 2 3 [4 5]] into [1 2 3 4 5]? |
| 23:59 | oracle | mapcat doesn't work since every element need to be a seq |
| 23:59 | oracle | but only [4 5] is a seq |