In JVM, we can assume (or should implement it in a way) that objects representing resource release the resource upon object's finalize method. If you push resource into the scope, it is not GCed until the scope ends. How about pushing to scope weak refs to resources instead?
JW On Sun, Oct 13, 2013 at 1:34 PM, Paul Stadig <p...@stadig.name> wrote: > No, I just implemented a simple intuitive scope, which looks like it is > about the same as the basic idea there. There are some interesting > ideas/questions about how scopes work across threads and how consumers can > pass the buck for resource clean up to an enclosing scope (like exception > handling). > > In my case I explicitly don't handle extending scopes to child threads > (for now). If the bindings convey to a child thread and you try to add an > object to the current scope, then you'll get an exception for trying to > set! a conveyed binding. > > I'm not sure about the idea for passing resource clean up to an enclosing > scope. I'd have to consider the problem and potential solutions before I > could form an opinion. > > That's not to say that these things are bad ideas or that some version of > them won't end up in the library. I just wanted a minimal implementation of > a scoping concept. It can evolve from there. > > > Paul > > > On Sat, Oct 12, 2013 at 10:11 AM, Jozef Wagner <jozef.wag...@gmail.com>wrote: > >> Is it based on http://dev.clojure.org/display/design/Resource+Scopes ? >> >> On Friday, October 11, 2013 3:54:59 PM UTC+2, Paul Stadig wrote: >>> >>> It separates the resource management from the creation and lexical >>> binding of resources. You can create a scope high up in the call stack, and >>> within the dynamic extent of that scope you can create resources, return >>> them from functions and freely use them; when the scope eventually exits, >>> then the resources will be cleaned up. >>> >>> This library does also generalize a bit to allow you to register an >>> object and a clean up function, or even just a thunk to get called when the >>> scope exits. >>> >>> On Friday, October 11, 2013 7:56:52 AM UTC-4, Cedric Greevey wrote: >>>> >>>> What does this do that (with-open ...) doesn't do? Generalize to other >>>> cleanup methods than (.close x)? >>>> >>>> >>>> On Fri, Oct 11, 2013 at 6:36 AM, Paul Stadig <pa...@stadig.name> wrote: >>>> >>>>> I have released version 0.1.0 of scopes, a little library for resource >>>>> scopes. It can be used to establish a resource scope with the >>>>> with-resource-scope macro. Within the dynamic extent of that macro one can >>>>> register a resource with the scoped! function so that when the macrco >>>>> block >>>>> goes out of scope .close is called on the registered resource. >>>>> >>>>> An object and function can also be registered with (scoped! x (fn [x] >>>>> ...)) so that when the macro block goes out of scope the function will be >>>>> called and given x as an argument. >>>>> >>>>> There is also a shorthand function called scoped-thunk! that will >>>>> register a thunk (a function taking no arguments) to be called when the >>>>> macro block goes out of scope. >>>>> >>>>> The scopes library also defines a function named closeable? that will >>>>> return true if its argument implements java.lang.AutoCloseable. >>>>> >>>>> Because scopes uses the java.lang.AutoCloseable interface and the >>>>> exception supression mechanism, it is only compatible with Java 7. >>>>> >>>>> Finally, there is also a scopes-magic artifact, and when it is on the >>>>> classpath it will automatically pull in the scopes library and add >>>>> with-resource-scope, scoped!, scoped-thunk!, and closeable? to >>>>> clojure.core >>>>> so that they are automatically available everywhere with out having to be >>>>> imported. I'm not saying that this is necessarily a good idea, but there >>>>> it >>>>> is. :) >>>>> >>>>> https://clojars.org/pjstadig/**scopes<https://clojars.org/pjstadig/scopes> >>>>> https://clojars.org/pjstadig/**scopes-magic<https://clojars.org/pjstadig/scopes-magic> >>>>> >>>>> >>>>> Paul >>>>> >>>>> -- >>>>> -- >>>>> 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 >>>>> 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 >>>>> 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. >>>>> 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 a topic in the >> Google Groups "Clojure" group. >> To unsubscribe from this topic, visit >> https://groups.google.com/d/topic/clojure/qPUd3AEVxT8/unsubscribe. >> To unsubscribe from this group and all its topics, 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. > -- -- You received this message because you are subscribed to the Google Groups "Clojure" group. 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