Re: What is the status of Clojure on LLVM or C?
On Friday, March 29, 2013 5:37:19 PM UTC+1, Herwig Hochleitner wrote: 2013/3/29 Marko Topolnik marko.t...@gmail.com javascript: Yes, you are involving Clojure startup here, which turns the tables altogether. This is far more work than just Java startup: all the namespaces must be initialized: all their def'd values calculated at runtime and assigned. Some of these may involve quite heavyweight service startup. This is the real issue in the Clojure startup story: it is not aggressively optimized towards zero startup time. It is a problem that carries over to other underlying implementations. The opposite is also true and weighs more heavy in this case, I think. Java is not optimized for good startup times. In particular, you can't embed any composite constants in byte code. Not even arrays. That means every last piece of metadata has to be allocated and built from scratch at startup. Every class for every toplevel fn has to be loaded (a process that involves deserialization aswell), initialized and instantiated. In a native code implementation of clojure, all the statically known functions, data and metadata structures could be directly embedded into the binary. Thus the init cost of a namespace with defn as the only toplevel forms could be near zero. An excellent point. Indeed, the semantics of the JVM are not specfiically geared towards quick startup. Do mind, however, that this is just specification we're talking about. An implementation may perform any optimization as long as it maintains the semantics. As an obvious example, take the startup of the JVM itself, which loads and initializes many hundreds of classes, and sets up a myriad of internal datastructures, within 100-200 ms. This kind of optimization is unfortunately not something client code can participate in, and that's where many problems start. Clojure would basically need its own custom JVM derivation which would provide an accessible way to fossilize a namespace and turn it into a binary blob that can be loaded in microsecoonds, resulting in a fully initialized image in memory. At a certain point in this departure from the JVM comes a moment where it is saner to start from scratch and build your own runtime, but that means you undo some 15 years of experience in building and optimizing a runtime for heayweight production systems. Some lessons can be carried over, but a huge spectrum of fine detials will be left for you to reinvent. As long as the JVM is alive and strong I doubt we shall ever see a native implementation that wouldn't cause frustration to its users, because it won't be the universally best choice. For many years to come nothing will be able to dethrone the JVM at the server side, where startup time means nothing and long-running stability is precious. So whatever runtime you choose, it will take you only that far before its specific limitations start giving you a headache. But hey, that's life: no language has conquered all the bases. Otherwise C would by now be just a tale from the elders. -marko -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: Clojure Style Guide
I agree - I thoroughly enjoyed this. On 30 March 2013 08:45, Alan Thompson thompson2...@gmail.com wrote: Hey - Just saw a nice article on this in (def newsletter) . It looks like quite a good reference on the subject. https://github.com/bbatsov/clojure-style-guidehttps://github.com/bbatsov/clojure-style-guide#mutation Alan Thompson -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out. -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Problem with map (only when running on browser)
I have the following code: (defn log-call [call] (.log js/console (pr-str call))) (defn generate-report [] ;; Get the data from the textarea calls_log (let [all-calls (.split (.-value (.getElementById js/document calls_log)) \n) [calls-headers calls-log] all-calls] ; Output all calls to the console log ;(.log js/console (pr-str calls-log (map log-call calls-log))) That code works on the REPL connected to the browser, and the date is displayed on the console. However, the compiled code doesn't run on the browser. I've tried debugging it with Chrome, but I'm not getting any errors, and I don't really know what's going on when following it step by step. If I comment the last line and uncomment the second to last, the code works on the browser. So basically if I don't do the map, it works. I am very confused. I only started using ClojureScript today, and already had a bunch of problems (including not being able to get domina 1.0.2-SNAPSHOT to work, trying to follow the moder_cljs tutorial), so I would really appreciate some help with this. Thank you very much! Nico -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: [ANN] Pedestal Application Framework
Cedric Greevey cgree...@gmail.com writes: It's a definite improvement ... but please print and sign the agreement, then scan and mail? There are a growing number of people that do *everything* online, to the point of not having a printer, not having a scanner, or not having either. Of course, the same people tend to have trouble with the quaint notion that a funny-looking squiggle emitted by pen onto paper is somehow a securer form of authentication than a 128-bit cryptographic signature of a document hash. :) -- Those people may be interested in sites like https://www.hellofax.com/ when faced with needing to print, sign, and scan some paper-trail :P -- Jeremiah Dodds blog : http://jdodds.github.com github : https://github.com/jdodds freenode/skype : exhortatory twitter: kaens -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: Apply elements in a vector as arguments to function
ClojureDocs currently show just the original docstring followed by user-contributed examples. I think a lot of readers would benefit from somethig like this: apply (apply f args* argseq) *Scripture:* Applies fn f to the argument list formed by prepending args to argseq. *Interpretation: *The first argument (f) is a function and the last argument is a sequence (argseq). Calls f with elements of argseq as its arguments. If more arguments are specified (args*), they are added to the beginning of the argseq to form the complete argument list with which f is called. * * *Examples:* (as usual) -marko On Wednesday, March 27, 2013 11:33:04 AM UTC+1, Marko Topolnik wrote: Now that Michael mentioned it, the docstring of *apply* says Applies fn f to the argument list formed by prepending intervening arguments to args. I challenge any Clojure newbie to decipher this Hickeyism for me. This is of course no exception; most of clojure.core is like that. I can personally testify to having learned (and *had to* learn) much more from source code than from docstrings. M-. has always been my best friend; C-d C-d came merely as a hint from Rich while solving the compile me in your head puzzle. -marko On Wednesday, March 27, 2013 11:17:05 AM UTC+1, Ryan wrote: The idea that people should read the source to get reasonably straightforward stuff done is wrong and does a lot of long term damage to the community. I believe Jim meant to check the source to figure out how does it work, not that the way it's implemented is the most proper way to implement it. If that's not what you wanted to point out can you please explain? On Wednesday, March 27, 2013 5:13:35 AM UTC+2, Michael Klishin wrote: 2013/3/27 Jim - FooBar(); jimpi...@gmail.com aaa see? always check the docs first and the sources second (if available)...I should have done that as well :) Definitely don't just check the sources and think it's something normal. Complain loudly to maintainers on this list that their documentation has gaps and they should clarify this and that. The idea that people should read the source to get reasonably straightforward stuff done is wrong and does a lot of long term damage to the community. -- MK http://github.com/michaelklishin http://twitter.com/michaelklishin -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: Problem with map (only when running on browser)
;(.log js/console (pr-str calls-log (map log-call calls-log))) map is lazily evaluated, so if you never read it's result nothing happens. You can force evaluation with doall (and variants) so... (doall (map log-call calls-log)) will behave as you expect. -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: would FixedThreadPool-backed reducers make sense?
The implementation of Clojure sequence library predates protocols. This is, however, the way forward, at least in clojurescript : https://github.com/clojure/clojurescript/blob/master/src/cljs/cljs/core.cljs#L191 On 28 March 2013 14:49, vemv v...@vemv.net wrote: I recall from Rich's presentation on reducers (and it's intuitively true anyway) that FJ is not well suited to all workloads: uniform ones would do just fine with a fixed allocation of tasks to threads. I believe the tradeoff in that case is that one has to manage parallelism very explicitly. Now, is it feasible to provide a reducers implementation backed by a fixed thead pool? How well would it perform (provided the workload is suitable)? Similarly, I'd find tempting (just if a little crazy) to define clj's seq library (map, filter, reduce...) as a huge protocol, providing e.g. simple-lazy, chunked, FJ, and fixed-thread-pool implementations. -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out. -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: Invoke a specific multimethod
On Mar 30, 2013, at 12:00 AM, George Oliver wrote:
On Friday, March 29, 2013 6:19:19 PM UTC-7, JvJ wrote:
Is it possible to invoke a particular multimethod and bypass the dispatch
function?
For instance, suppose that I have a multimethod with a dispatch value of
::foo, and it's a really complex method.
Now, I want all cases where the dispatch function returns nil to use the same
multimethod. Is there a way I can intercept the nil and
pass it directly on to the ::foo multimethod?
You could use the default multimethod to catch nil, and then call the multi
with ::foo.
That will only work if the dispatch fn is identity or similar.
If you control the dispatch fn, then you don't need to intercept nil -- just
returning ::foo from the dispatch fn when it might otherwise return nil will
get you to the method you want.
If you *don't* control the dispatch fn, but you're providing the methods for
:foo and nil, then you can use `get-method` to obtain the method associated
with a particular dispatch value:
= (defmulti foo :bar)
#'user/foo
= (defmethod foo :baz
[x]
(str x))
#MultiFn clojure.lang.MultiFn@6194a872
= (defmethod foo :default
[x]
((get-method foo :baz) x))
#MultiFn clojure.lang.MultiFn@6194a872
= (foo {:bar :baz})
{:bar :baz}
= (foo {:some :other :value :here})
{:some :other, :value :here}
Of course, if the functionality you need is available as a separate top-level
fn, and you can avoid the extra effective dispatch through the multimethod, all
the better.
Cheers,
- Chas
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Re: Problem with map (only when running on browser)
When you want a side effect and don't care about return values, it's idiomatic to use doseq. (doseq [c calls-log] (log-call c)) On Mar 30, 2013 4:23 AM, Neale Swinnerton ne...@isismanor.com wrote: ;(.log js/console (pr-str calls-log (map log-call calls-log))) map is lazily evaluated, so if you never read it's result nothing happens. You can force evaluation with doall (and variants) so... (doall (map log-call calls-log)) will behave as you expect. -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out. -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
ANN: no.disassemble, a runtime bytecode disassembler
I made a little proof of concept last night. You could always look at
bytecode that clojure emits in few ways, you can either hack the compiler
yourself, or force AOT in your project and use javap. The first approach
is a bit intrusive, and the second has a somewhat annoying turnaround time,
and won't work for any code that calls eval at runtime.
This takes another approach. It uses java's Instrumentation stuff, to
provide a hook into all classloading past the point at which it's loaded,
where I store off all the bytes of defined classes into a big
ConcurrentHashMap. Then I use eclipse.jdt.core's disassembler
functionality to print out the bytecode.
There's a nice lein-plugin that adds the dependency to your project and
looks itself up in order to add the appropriate -javaagent flag to your jvm
startup options.
Now you can do something like this:
user= (require 'no.disassemble)
nil
user= (in-ns 'no.disassemble)
#Namespace no.disassemble
no.disassemble= (println (disassemble (fn [])))
// Compiled from NO_SOURCE_FILE (version 1.5 : 49.0, super bit)
public final class no.disassemble$eval1174$fn__1175 extends
clojure.lang.AFunction {
// Method descriptor #7 ()V
// Stack: 0, Locals: 0
public static {};
0 return
Line numbers:
[pc: 0, line: 1]
// Method descriptor #7 ()V
// Stack: 1, Locals: 1
public disassemble$eval1174$fn__1175();
0 aload_0
1 invokespecial clojure.lang.AFunction() [10]
4 return
Line numbers:
[pc: 0, line: 1]
// Method descriptor #12 ()Ljava/lang/Object;
// Stack: 1, Locals: 1
public java.lang.Object invoke();
0 aconst_null
1 areturn
Line numbers:
[pc: 0, line: 1]
Local variable table:
[pc: 0, pc: 1] local: this index: 0 type: java.lang.Object
}
nil
no.disassemble=
Potential use cases:
Writing fast code faster.
Proving to newbies that clojure is not interpreted, further evidence of
eval's coolness.
Checking to make sure primitives are being used where you expect.
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Re: ANN: no.disassemble, a runtime bytecode disassembler
https://github.com/gtrak/no.disassemble/
On Saturday, March 30, 2013 9:06:25 AM UTC-4, Gary Trakhman wrote:
I made a little proof of concept last night. You could always look at
bytecode that clojure emits in few ways, you can either hack the compiler
yourself, or force AOT in your project and use javap. The first approach
is a bit intrusive, and the second has a somewhat annoying turnaround time,
and won't work for any code that calls eval at runtime.
This takes another approach. It uses java's Instrumentation stuff, to
provide a hook into all classloading past the point at which it's loaded,
where I store off all the bytes of defined classes into a big
ConcurrentHashMap. Then I use eclipse.jdt.core's disassembler
functionality to print out the bytecode.
There's a nice lein-plugin that adds the dependency to your project and
looks itself up in order to add the appropriate -javaagent flag to your jvm
startup options.
Now you can do something like this:
user= (require 'no.disassemble)
nil
user= (in-ns 'no.disassemble)
#Namespace no.disassemble
no.disassemble= (println (disassemble (fn [])))
// Compiled from NO_SOURCE_FILE (version 1.5 : 49.0, super bit)
public final class no.disassemble$eval1174$fn__1175 extends
clojure.lang.AFunction {
// Method descriptor #7 ()V
// Stack: 0, Locals: 0
public static {};
0 return
Line numbers:
[pc: 0, line: 1]
// Method descriptor #7 ()V
// Stack: 1, Locals: 1
public disassemble$eval1174$fn__1175();
0 aload_0
1 invokespecial clojure.lang.AFunction() [10]
4 return
Line numbers:
[pc: 0, line: 1]
// Method descriptor #12 ()Ljava/lang/Object;
// Stack: 1, Locals: 1
public java.lang.Object invoke();
0 aconst_null
1 areturn
Line numbers:
[pc: 0, line: 1]
Local variable table:
[pc: 0, pc: 1] local: this index: 0 type: java.lang.Object
}
nil
no.disassemble=
Potential use cases:
Writing fast code faster.
Proving to newbies that clojure is not interpreted, further evidence of
eval's coolness.
Checking to make sure primitives are being used where you expect.
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Re: Problem with map (only when running on browser)
Thank you very much sw1nn and John, both worked great. This goes to show how much of a newb I am. Sorry if this is the wrong group (just realized it is the Clojure group and not Clojurescript one). BTW, it seems like knowing Clojure is a requirement to start using Clojurescript, do you guys know of any turorials/resources to learn Clojurescript that don't rely on previous Clojure knowledge? (so far I've seen Clojurescript One and Modern. Clojurescript One is way too much for starters, too many things going on at once. Modern is better, but I couldn't get domina 1.0.2-SNAPSHOT to be automatically fetched from Clojars, hence I got stuck). On Saturday, March 30, 2013 8:31:37 AM UTC-4, John Hume wrote: When you want a side effect and don't care about return values, it's idiomatic to use doseq. (doseq [c calls-log] (log-call c)) On Mar 30, 2013 4:23 AM, Neale Swinnerton ne...@isismanor.comjavascript: wrote: ;(.log js/console (pr-str calls-log (map log-call calls-log))) map is lazily evaluated, so if you never read it's result nothing happens. You can force evaluation with doall (and variants) so... (doall (map log-call calls-log)) will behave as you expect. -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clo...@googlegroups.comjavascript: Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+u...@googlegroups.com javascript: For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+u...@googlegroups.com javascript:. For more options, visit https://groups.google.com/groups/opt_out. -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: Problem with map (only when running on browser)
Clojurescript is Clojure...you may be able to skip some JVM idiosyncrasies but it's the same language - no way around that! Jim On 30/03/13 14:09, Nico wrote: Thank you very much sw1nn and John, both worked great. This goes to show how much of a newb I am. Sorry if this is the wrong group (just realized it is the Clojure group and not Clojurescript one). BTW, it seems like knowing Clojure is a requirement to start using Clojurescript, do you guys know of any turorials/resources to learn Clojurescript that don't rely on previous Clojure knowledge? (so far I've seen Clojurescript One and Modern. Clojurescript One is way too much for starters, too many things going on at once. Modern is better, but I couldn't get domina 1.0.2-SNAPSHOT to be automatically fetched from Clojars, hence I got stuck). On Saturday, March 30, 2013 8:31:37 AM UTC-4, John Hume wrote: When you want a side effect and don't care about return values, it's idiomatic to use doseq. (doseq [c calls-log] (log-call c)) On Mar 30, 2013 4:23 AM, Neale Swinnerton ne...@isismanor.com javascript: wrote: ;(.log js/console (pr-str calls-log (map log-call calls-log))) map is lazily evaluated, so if you never read it's result nothing happens. You can force evaluation with doall (and variants) so... (doall (map log-call calls-log)) will behave as you expect. -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clo...@googlegroups.com javascript: Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+u...@googlegroups.com javascript: For more options, visit this group at http://groups.google.com/group/clojure?hl=en http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+u...@googlegroups.com javascript:. For more options, visit https://groups.google.com/groups/opt_out https://groups.google.com/groups/opt_out. -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out. -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: ANN: no.disassemble, a runtime bytecode disassembler
On Sat, Mar 30, 2013 at 9:06 AM, Gary Trakhman gary.trakh...@gmail.comwrote : Potential use cases: Writing fast code faster. Proving to newbies that clojure is not interpreted, further evidence of eval's coolness. Checking to make sure primitives are being used where you expect. Scaring the bejesus out of Johnny 5. :) -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: Problem with map (only when running on browser)
On Sat, Mar 30, 2013 at 10:09 AM, Nico nbren...@gmail.com wrote: BTW, it seems like knowing Clojure is a requirement to start using Clojurescript, I think the general expectation has been that anyone using Clojurescript is likely to be using both. Maybe you should just learn Clojure? Between the many tutorial and documentation resources posted, try-clojure, and the lightweight IDE clooj, it shouldn't be too difficult. P.S. Please fix your linewrap. The long lines make it inconvenient to read this entire thread, at least in gmail's web interface. -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: Names and clojure.core
On Thursday, March 28, 2013 9:53:19 AM UTC-4, Michael Klishin wrote: 2013/3/28 Mark mjt...@gmail.com javascript: Do other people have this problem? Am I just too uncreative? Am I being too terse? Simply exclude some clojure.core functions in your namespace declaration and use them as clojure.core/... if you need them. It's perfectly fine to use names such as find,get and so on in your own namespaces. http://clojure-doc.org/articles/language/namespaces.html#the_referclojure_helper_form My only complaint about doing this is that it would cause me to do a double-take every time I saw the clojure.core name (ex. Wait --- is that the clojure.core foo or the local foo? Lemme just glance around...). I'd suspect that using slightly longer and hyphenated names would be easier to read and more descriptive, and it only require typing a few extra characters (`dna-seq`, `base-pairs`, etc.). ---John -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: ANN: no.disassemble, a runtime bytecode disassembler
2013/3/30 Gary Trakhman gary.trakh...@gmail.com Potential use cases: Writing fast code faster. Proving to newbies that clojure is not interpreted, further evidence of eval's coolness. Checking to make sure primitives are being used where you expect. Great idea. This kind of information is very valuable when doing optimization work and also helps understand how the compiler works. -- MK http://github.com/michaelklishin http://twitter.com/michaelklishin -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Getting array length
Why doesn't (.length (int-array 5)) work? Why should I use alength or count instead? -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: Getting array length
It seems that .length isn't a real field at the JVM level - it is just part of the Java - the language. The JVM has a special arraylength op-code for getting the length of arrays. On Sat, Mar 30, 2013 at 5:17 PM, Alice dofflt...@gmail.com wrote: Why doesn't (.length (int-array 5)) work? Why should I use alength or count instead? -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out. -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
ANN: Windows installer for Leiningen
Hi, I've put together an installer for Leiningen on Windows: http://leiningen-win-installer.djpowell.net/ Hopefully it should make it a bit easier for Windows people to get Leiningen and a Clojure repl up and running. It requires a JDK to be installed first, but other than that there aren't any dependencies. It should work on Windows XP and above, 32-bit or 64-bit. With or without powershell available. The installer should take the hassle out of setting up paths and environment variables, and changing them when new JDKs are installed. The current version is beta1. If you've got any feedback then give me an email. -- Dave -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: Getting array length
use the function alength Alice writes: Why doesn't (.length (int-array 5)) work? Why should I use alength or count instead? -- -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: Quirk with printing regexps
On Thu, Mar 28, 2013 at 7:52 PM, Mikhail Kryshen mikh...@kryshen.netwrote: On Thu, 28 Mar 2013 17:08:46 -0700 Mark Engelberg mark.engelb...@gmail.com wrote: Bug or feature? Certainly a feature for complex patterns with whitespace and embedded comments. For example, the following regexp parses line in Combined Log Format used by Apache httpd and other web servers: (def clf-pattern #(?x)^ (\S*)\s # remote host (\S*)\s # remote logname (\S*)\s # remote user \[([^\]]+)\]\s # time the request was received \([^\\\]*(?:\\.[^\\\]*)*)\\s # first line of request (\S*)\s # status (\S*)\s # size of response in bytes \([^\\\]*(?:\\.[^\\\]*)*)\\s # referer \([^\\\]*(?:\\.[^\\\]*)*)\ # user-agent \s*$) I appreciate this information. It's useful to know this subtle difference in how regular expressions store newlines depending on whether it was entered as an actual newline character or an escape sequence designating a newline character, and that this difference manifests when the regex is prepended with (?x). I see how this makes it easier to define a regexp using linebreaks for clarity, and then signaling that those linebreaks are not intended to be taken literally. You probably would not want it to be printed in a single line. Yes, but I would want it to pr in a single line. This is one of the key differences between print and pr. print is more human readable and pr is a more machine-like view of the contents. To me, one of the main things that entails is that whitespace should be printed in a way that you can see exactly what is going on and how it is stored. Compare (pr abc def) to (print abc def) then compare (pr #abc def) to (print #abc def) I think it is fairly clear that regular expressions *should* behave the same way as strings here, and that pr should be printing whitespaces in a visible, escaped way. Based on everything you've told me, I'd still classify the current behavior as a bug/oversight, not a feature. -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: ANN: no.disassemble, a runtime bytecode disassembler
Gary Trakhman gary.trakh...@gmail.com writes: I made a little proof of concept last night. You could always look at bytecode that clojure emits in few ways, you can either hack the compiler yourself, or force AOT in your project and use javap. The first approach is a bit intrusive, and the second has a somewhat annoying turnaround time, and won't work for any code that calls eval at runtime. This takes another approach. It uses java's Instrumentation stuff, to provide a hook into all classloading past the point at which it's loaded, where I store off all the bytes of defined classes into a big ConcurrentHashMap. Then I use eclipse.jdt.core's disassembler functionality to print out the bytecode. The Ritz' disassembler uses jpda to access the bytecode. Not yet ported to ritz-nrepl though. Hugo -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: Quirk with printing regexps
On Thu, Mar 28, 2013 at 6:36 PM, Andy Fingerhut andy.finger...@gmail.comwrote: (defn print-regex-my-way [re] (print #regex ) (pr (str re))) That might be closer to what you want. Yes. That does the trick. That extra level of converting the regular expression to a string does the trick because pr does the right thing with strings, but not with regexes. I'd classify pr's different behavior on regexes as a bug, but this is an effective workaround. Thanks. -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: ANN: Windows installer for Leiningen
Nice work! On Saturday, March 30, 2013 1:39:12 PM UTC-4, David Powell wrote: Hi, I've put together an installer for Leiningen on Windows: http://leiningen-win-installer.djpowell.net/ Hopefully it should make it a bit easier for Windows people to get Leiningen and a Clojure repl up and running. It requires a JDK to be installed first, but other than that there aren't any dependencies. It should work on Windows XP and above, 32-bit or 64-bit. With or without powershell available. The installer should take the hassle out of setting up paths and environment variables, and changing them when new JDKs are installed. The current version is beta1. If you've got any feedback then give me an email. -- Dave -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Wrong number of args (0) passed to: PersistentArrayMap
I understand that this error frequently appears when someone accidentally
puts a map into the first position of a list, and so the map is called as a
function:
Exception in thread Thread-13 clojure.lang.ArityException: Wrong number
of args (0) passed to: PersistentArrayMap
But I am not sure why that is happening to me in the function below. Assume
I have a data structure that looks like:
(def initial-data
:slides {
:who-is-going-to-summer-camp { :public-text Who is going
to summer camp?
:order-of-appearance 1
:to-be-deleted true}
:what-is-your-budget { :public-text What is your budget?
:order-of-appearance 2}
}
:answers {
:under-one-thousand-dollars { :public-text Under $1,000
dollars?
:slides-id :what-is-your-budget }
:over-one-thousand-dollars { :public-text Over $1,000
dollars?
:slides-id :what-is-your-budget }
}
;; etc
)
(defn delete-those-items-in-the-model-that-are-scheduled-to-be-deleted []
;; 2013-02-28 - THIS FUNCTION IS CALLED AT STARTUP AND RUNS IN ITS OWN
THREAD, REPEATING ENDLESSLY.
(doseq [x (keys (@um/interactions))]
(doseq [m (vals (um/get-from-model [x]))]
(if (:to-be-deleted m)
(do
(um/delete-this-item m)
(monger/remove-this-item m)
(. java.lang.Thread sleep 90)
(delete-those-items-in-the-model-that-are-scheduled-to-be-deleted))
Assume um/get-from-model is almost the same as get-in. Assume initial-data
is stored in the atom um/interactions. Where am I calling a map as a
function here?
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Re: Wrong number of args (0) passed to: PersistentArrayMap
On Sat, Mar 30, 2013 at 9:49 PM, larry google groups
lawrencecloj...@gmail.com wrote:
(def initial-data
:slides {
:who-is-going-to-summer-camp { :public-text Who is going to
summer camp?
:order-of-appearance 1
:to-be-deleted true}
:what-is-your-budget { :public-text What is your budget?
:order-of-appearance 2}
}
:answers {
:under-one-thousand-dollars { :public-text Under $1,000
dollars?
:slides-id
:what-is-your-budget }
:over-one-thousand-dollars { :public-text Over $1,000
dollars?
:slides-id
:what-is-your-budget }
}
;; etc
)
(defn delete-those-items-in-the-model-that-are-scheduled-to-be-deleted []
;; 2013-02-28 - THIS FUNCTION IS CALLED AT STARTUP AND RUNS IN ITS OWN
THREAD, REPEATING ENDLESSLY.
(doseq [x (keys (@um/interactions))]
(doseq [m (vals (um/get-from-model [x]))]
(if (:to-be-deleted m)
(do
(um/delete-this-item m)
(monger/remove-this-item m)
(. java.lang.Thread sleep 90)
(delete-those-items-in-the-model-that-are-scheduled-to-be-deleted))
Assume um/get-from-model is almost the same as get-in. Assume initial-data is
stored in the atom um/interactions. Where am I calling a map as a function
here?
(@um/interactions) perhaps?
Lars Nilsson
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Re: Wrong number of args (0) passed to: PersistentArrayMap
It's so obvious when you point it out.
On Saturday, March 30, 2013 10:02:30 PM UTC-4, Lars Nilsson wrote:
On Sat, Mar 30, 2013 at 9:49 PM, larry google groups
lawrenc...@gmail.com javascript: wrote:
(def initial-data
:slides {
:who-is-going-to-summer-camp { :public-text Who is
going to summer camp?
:order-of-appearance 1
:to-be-deleted true}
:what-is-your-budget { :public-text What is your
budget?
:order-of-appearance
2}
}
:answers {
:under-one-thousand-dollars { :public-text Under
$1,000 dollars?
:slides-id
:what-is-your-budget }
:over-one-thousand-dollars { :public-text Over
$1,000 dollars?
:slides-id
:what-is-your-budget }
}
;; etc
)
(defn delete-those-items-in-the-model-that-are-scheduled-to-be-deleted
[]
;; 2013-02-28 - THIS FUNCTION IS CALLED AT STARTUP AND RUNS IN ITS OWN
THREAD, REPEATING ENDLESSLY.
(doseq [x (keys (@um/interactions))]
(doseq [m (vals (um/get-from-model [x]))]
(if (:to-be-deleted m)
(do
(um/delete-this-item m)
(monger/remove-this-item m)
(. java.lang.Thread sleep 90)
(delete-those-items-in-the-model-that-are-scheduled-to-be-deleted))
Assume um/get-from-model is almost the same as get-in. Assume
initial-data is stored in the atom um/interactions. Where am I calling a
map as a function here?
(@um/interactions) perhaps?
Lars Nilsson
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Re: Floating point comparator issue?
That makes sense. Thanks. On Friday, 29 March 2013 22:21:21 UTC-4, Alan Malloy wrote: Comparator.compare returns an int. (int 0.2) and (int -0.2) both return 0. Thus, your comparator is returning 0, saying I don't care what order these go in. On Mar 29, 6:44 pm, JvJ kfjwhee...@gmail.com wrote: Alright check this out: ;; Normal subtraction as comparator sorts in ascending order (sort-by identity #(- %1 %2) [1 -1]) (-1 1) ;; Reverse subtraction as comparator sorts in descending order (sort-by identity #(- %2 %1) [1 -1]) (1 -1) ;;=== ;; And now with values of -0.1, 0.1 ;; Reverse subtraction as comparator sorts in descending order (sort-by identity #(- %2 %1) [0.1 -0.1]) (0.1 -0.1) ;; Normal subtraction STILL sorts in descending order?? (sort-by identity #(- %1 %2) [0.1 -0.1]) (0.1 -0.1) -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups Clojure group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: Invoke a specific multimethod
get-method. Thanks, that was exactly what I was looking for!
On Saturday, 30 March 2013 07:20:54 UTC-4, Chas Emerick wrote:
On Mar 30, 2013, at 12:00 AM, George Oliver wrote:
On Friday, March 29, 2013 6:19:19 PM UTC-7, JvJ wrote:
Is it possible to invoke a particular multimethod and bypass the dispatch
function?
For instance, suppose that I have a multimethod with a dispatch value of
::foo, and it's a really complex method.
Now, I want all cases where the dispatch function returns nil to use the
same multimethod. Is there a way I can intercept the nil and
pass it directly on to the ::foo multimethod?
You could use the default multimethod to catch nil, and then call the
multi with ::foo.
That will only work if the dispatch fn is identity or similar.
If you control the dispatch fn, then you don't need to intercept nil --
just returning ::foo from the dispatch fn when it might otherwise return
nil will get you to the method you want.
If you *don't* control the dispatch fn, but you're providing the methods
for :foo and nil, then you can use `get-method` to obtain the method
associated with a particular dispatch value:
= (*defmulti* foo :bar)
#'user/foo
= (*defmethod* foo :baz
[x]
(str x))
#MultiFn clojure.lang.MultiFn@6194a872
= (*defmethod* foo :default
[x]
((get-method foo :baz) x))
#MultiFn clojure.lang.MultiFn@6194a872
= (foo {:bar :baz})
{:bar :baz}
= (foo {:some :other :value :here})
{:some :other, :value :here}
Of course, if the functionality you need is available as a separate
top-level fn, and you can avoid the extra effective dispatch through the
multimethod, all the better.
Cheers,
- Chas
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Re: Invoke a specific multimethod
Also, nice syntax highlighting! How'd you do that?
On Saturday, 30 March 2013 23:54:03 UTC-4, JvJ wrote:
get-method. Thanks, that was exactly what I was looking for!
On Saturday, 30 March 2013 07:20:54 UTC-4, Chas Emerick wrote:
On Mar 30, 2013, at 12:00 AM, George Oliver wrote:
On Friday, March 29, 2013 6:19:19 PM UTC-7, JvJ wrote:
Is it possible to invoke a particular multimethod and bypass the
dispatch function?
For instance, suppose that I have a multimethod with a dispatch value of
::foo, and it's a really complex method.
Now, I want all cases where the dispatch function returns nil to use the
same multimethod. Is there a way I can intercept the nil and
pass it directly on to the ::foo multimethod?
You could use the default multimethod to catch nil, and then call the
multi with ::foo.
That will only work if the dispatch fn is identity or similar.
If you control the dispatch fn, then you don't need to intercept nil --
just returning ::foo from the dispatch fn when it might otherwise return
nil will get you to the method you want.
If you *don't* control the dispatch fn, but you're providing the methods
for :foo and nil, then you can use `get-method` to obtain the method
associated with a particular dispatch value:
= (*defmulti* foo :bar)
#'user/foo
= (*defmethod* foo :baz
[x]
(str x))
#MultiFn clojure.lang.MultiFn@6194a872
= (*defmethod* foo :default
[x]
((get-method foo :baz) x))
#MultiFn clojure.lang.MultiFn@6194a872
= (foo {:bar :baz})
{:bar :baz}
= (foo {:some :other :value :here})
{:some :other, :value :here}
Of course, if the functionality you need is available as a separate
top-level fn, and you can avoid the extra effective dispatch through the
multimethod, all the better.
Cheers,
- Chas
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Re: hash-map initialization issue
Here's a cheezy hack, use identity.
#(identity {:foo %})
On Thursday, 28 March 2013 17:51:10 UTC-4, Ryan wrote:
Thanks for your explanation Jonathan. I am still a bit confused however
what is the proper solution here. Should i use an anonymous function
instead to do what I want or can it be done with the #() syntax?
Hyphens is my preferred way as well, but, those keys represent sql columns
which they use underscore so I gotta go with underscores in order code to
match them :)
Ryan
On Thursday, March 28, 2013 11:24:38 PM UTC+2, Jonathan Fischer Friberg
wrote:
It's because the #() syntax always calls the content as a function.
So #(...) is the same as (fn [] (...)). In your case,
#({:foo_id foo-id (keyword a-keyword) (:BAR_KEY %)})
is the same as:
(fn [%] ({:foo_id foo-id (keyword a-keyword) (:BAR_KEY %)}))
Note the extra () around {}. In other words, your map is called
as a function.
Maps can normally be called as functions, like this:
({:hello :world} :hello)
= :world
That's why you get the Wrong number of args error
(and not a a map is not a function error).
Hope that makes sense.
Btw, hyphen is normally used instead of underscore
in both variables and keywords. Just a slight style
issue, but maybe you had your reasons. :)
Jonathan
On Thu, Mar 28, 2013 at 10:16 PM, Ryan areka...@gmail.com wrote:
Hello!
I am having a small issue with a hash-map initialization and I am
failing to understand why. I have the following situation:
(def a-list '({:BAR_KEY bar-value}, {:BAR_KEY another-value}))
(defn my-function [foo-id a-keyword a-list]
(map #({:foo_id foo-id (keyword a-keyword) (:BAR_KEY %)}) a-list))
So, by running the above function like this:
(my-function 5 my_keyword a-list)
I get the following error:
*clojure.lang.ArityException: Wrong number of args (0) passed to:
PersistentArrayMap*
I am trying to get the following result:
({:foo_id 5 :my_keyword bar-value}, {:foo_id 5 :my_keyword
another-value})
Any ideas? I have played around in repl for the last 2 hrs but I haven't
found the proper way to do this.
Thank you for your time :)
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Re: Sweet-expressions
Once you write enough lisp, eliminating parens becomes more trouble than
it's worth.
Also the guy who did this has the same name as my dad? I'm ashamed.
On Monday, 25 March 2013 06:52:23 UTC-4, poetix wrote:
I really like the look of this:
http://readable.sourceforge.net/
which defines a completely reversible transformation between e.g.
define fibfast(n)
if {n 2}
n
fibup(n 2 1 0)
and
(define (fibfast n)
(if ( n 2)
n
(fibup n 2 1 0)))
and wonder how difficult it would be to support it (or something like it)
in/for Clojure. A coffeescript-like approach might be a good first step.
Any thoughts?
Dominic
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