There's nothing like a Learn You A core.logic, but Ambrose and Ryan Senior's tutorials are pretty great.
https://github.com/frenchy64/Logic-Starter/wiki http://objectcommando.com/ David On Sat, Nov 5, 2011 at 3:34 PM, Michael Jaaka <michael.ja...@googlemail.com>wrote: > > Btw. Is there any fine tutorial for core.logic? By fine I mean > something like learn haskell for great good. > > On 5 Lis, 20:26, Michael Jaaka <michael.ja...@googlemail.com> wrote: > > Now is ok, easy to grasp. How the lein dep declaration and clj import > > looks? > > Thank you both. > > > > On 5 Lis, 20:11, David Nolen <dnolen.li...@gmail.com> wrote: > > > > > > > > > > > > > > > > > I would probably write the code like this: > > > > > (defrel permission role op state) > > > > > (defn add-permision [roles ops states] > > > (doseq [r roles o ops s states] > > > (fact permission r o s))) > > > > > (add-permision #{:admin :operator} #{:reject :accept} #{:applied}) > > > > > (defn permissiono [role op state] > > > (run* [q] > > > (permission role op state) > > > (== q {:role role :op op :state state}))) > > > > > (permissiono :admin (lvar) (lvar)) > > > > > ;; ({:role :admin, :op :reject, :state :applied} > > > ;; {:role :admin, :op :accept, :state :applied}) > > > > > We can use (lvar) for wildcards. If nothing can satisfy the query > you'll > > > get back an empty sequences. > > > > > What in particular do you find unsatisfactory about this interface? > > > > > On Sat, Nov 5, 2011 at 2:46 PM, Michael Jaaka > > > <michael.ja...@googlemail.com>wrote: > > > > > > Thanks, it gave me insight into that framework. > > > > Unfortunately it doesn't look friendly in usage. > > > > Looks like there is a place for a clojure lib or wrapper around > > > > core.logic. > > > > It would be nice if it could answer to questions also in terms of > > > > truth. > > > > > > On 5 Lis, 18:24, Ambrose Bonnaire-Sergeant > > > > <abonnaireserge...@gmail.com> wrote: > > > > > I gave the wildcard requirement a bit of thought, no inspiration > at the > > > > > moment. > > > > > > > Maybe someone else can suggest a strategy. > > > > > > > Ambrose > > > > > > > On Sun, Nov 6, 2011 at 1:14 AM, Ambrose Bonnaire-Sergeant < > > > > > > > abonnaireserge...@gmail.com> wrote: > > > > > > Hey Michael, > > > > > > > > Here's a solution using core.logic. > > > > > > > > ;; We can define a "permission" relation with "defrel". > > > > > > > > (defrel permission roles ops state) > > > > > > > > ;; and a helper function to add each combination of permissions > > > > > > > > (defn add-permision [roles ops states] > > > > > > (for [r roles > > > > > > o ops > > > > > > s states] > > > > > > (fact permission r o s))) > > > > > > > > ;; Here is your first example > > > > > > > > (add-permision #{:admin :operator} #{:reject :accept} > #{:applied}) > > > > > > > > ;; Now lets ask what are the permissions for the :admin role > > > > > > > > logic-introduction.perm=> (run* [q] > > > > > > (fresh [ops states] > > > > > > (permission :admin ops > states) > > > > > > (== q [ops states]))) > > > > > > ([:reject :applied] [:accept :applied]) > > > > > > > > ;; Ask what permissions either a :admin or :operator role has > > > > > > > > logic-introduction.perm=> (run* [q] > > > > > > (fresh [role ops states] > > > > > > (conde > > > > > > ((== role :admin)) > > > > > > ((== role :operator))) > > > > > > (== q [ops states]) > > > > > > (permission role ops > states))) > > > > > > ([:reject :applied] [:accept :applied] [:reject :applied] > [:accept > > > > > > :applied]) > > > > > > > > Thanks, > > > > > > Ambrose > > > > > > > > On Sun, Nov 6, 2011 at 12:51 AM, Michael Jaaka < > > > > > > michael.ja...@googlemail.com> wrote: > > > > > > > >> Hi, > > > > > > > >> I would like to use logic programing to describe permissions. > The > > > > > >> definition is > > > > > > > >> We have set of triples which looks like: > > > > > >> Set of roles; set of operations; set of states > > > > > > > >> Triples are defined in scope of some entity with states, > wildcard is > > > > > >> defined with _ > > > > > > > >> All I need is to answer on some operation invocation if given > user > > > > > >> with his role is able to execute that operation for particular > entity > > > > > >> which is in one of its states > > > > > > > >> Example: > > > > > >> Roles: admin, operator, auditor > > > > > >> Entity: data form with states dirty, applied, rejected, executed > > > > > >> Operations on data form: reject, acept, list, enter > > > > > >> Triples of permissions: > > > > > >> admin, operator; reject, accept; applied > > > > > >> auditor, operator; list; _ > > > > > >> operator; enter; dirty > > > > > > > >> The additional question beside checking permission is: > > > > > >> What are operations avaiable for given role and given state of > entity > > > > > > > >> Any thoughts? Maybe core.logic? It seems that I know its > purpose but > > > > > >> don't know how to use it. > > > > > >> Thanks in advance. > > > > > > > >> -- > > > > > >> 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 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 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. 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