{"id":13646178,"url":"https://github.com/Malabarba/lazy-map-clojure","last_synced_at":"2025-04-21T17:32:13.563Z","repository":{"id":62433529,"uuid":"37992839","full_name":"Malabarba/lazy-map-clojure","owner":"Malabarba","description":"Create Clojure maps whose values are only calculated when accessed, either from data or from java objects.","archived":false,"fork":false,"pushed_at":"2020-05-27T01:43:32.000Z","size":72,"stargazers_count":49,"open_issues_count":1,"forks_count":5,"subscribers_count":4,"default_branch":"master","last_synced_at":"2025-04-14T15:59:57.222Z","etag":null,"topics":[],"latest_commit_sha":null,"homepage":null,"language":"Clojure","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"epl-1.0","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/Malabarba.png","metadata":{"files":{"readme":"README.org","changelog":null,"contributing":null,"funding":null,"license":"LICENSE","code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null}},"created_at":"2015-06-24T15:22:47.000Z","updated_at":"2024-04-27T10:50:02.000Z","dependencies_parsed_at":"2022-11-01T20:45:50.706Z","dependency_job_id":null,"html_url":"https://github.com/Malabarba/lazy-map-clojure","commit_stats":null,"previous_names":[],"tags_count":0,"template":false,"template_full_name":null,"repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/Malabarba%2Flazy-map-clojure","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/Malabarba%2Flazy-map-clojure/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/Malabarba%2Flazy-map-clojure/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/Malabarba%2Flazy-map-clojure/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/Malabarba","download_url":"https://codeload.github.com/Malabarba/lazy-map-clojure/tar.gz/refs/heads/master","host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":250100636,"owners_count":21374977,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2022-07-04T15:15:14.044Z","host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":[],"created_at":"2024-08-02T01:02:49.907Z","updated_at":"2025-04-21T17:32:10.494Z","avatar_url":"https://github.com/Malabarba.png","language":"Clojure","funding_links":[],"categories":["Clojure","Advanced datastructures"],"sub_categories":[],"readme":"#+OPTIONS: toc:nil num:nil\n#+TITLE: lazy-map [[https://travis-ci.org/Malabarba/lazy-map-clojure?branch%3Dmaster][https://secure.travis-ci.org/Malabarba/lazy-map-clojure.png?branch=master]] [[https://dry-clojure.herokuapp.com/repo/Malabarba/lazy-map-clojure/heads/master][https://img.shields.io/badge/dryness-68-97CA00.svg]] [[https://coveralls.io/github/Malabarba/lazy-map-clojure?branch=master][https://coveralls.io/repos/Malabarba/lazy-map-clojure/badge.svg?branch=master\u0026service=github]]\n\nCreate maps whose values are only calculated when accessed, either from data or from java objects.\nSupports both Clojure and Clojurescript!\n\n[[http://clojars.org/malabarba/lazy-map][file:https://clojars.org/malabarba/lazy-map/latest-version.svg]]\n\n[[http://malabarba.github.io/lazy-map-clojure/][Documentation]]\n\n** The [[http://malabarba.github.io/lazy-map-clojure/lazy-map.core.html#var-lazy-map][lazy-map]]\n\nThis macro is analogous to ~lazy-seq~. It takes a map (instead of a\nseq), but the value expressions you write aren't actually evaluated\nuntil they are accessed.\n\n#+BEGIN_SRC clojure\nuser\u003e (def my-map\n        (lazy-map\n         {:cause (do (println \"Getting Cause\")\n                     :major-failure)\n          :name (do (println \"Getting Name\")\n                    \"Some Name\")}))\n#'user/my-map\n\nuser\u003e (:name my-map)\nGetting Name\n\"Some Name\"\n\nuser\u003e (:name my-map)\n\"Some Name\"\n\nuser\u003e (:cause my-map)\nGetting Cause\n:major-failure\n\nuser\u003e (:cause my-map)\n:major-failure\n#+END_SRC\n\nYou can also assoc new keys into a LazyMap like a regular Clojure map.\nIf you assoc a ~delay~ it will act as a lazy value, and if you assoc\nanything else it acts as a regular value.\n\n#+BEGIN_SRC clojure\nuser\u003e (def new-map (-\u003e (assoc my-map :surname \"Malabarba\")\n                 (assoc :delayed-surname\n                        (delay (println \"Resolved\")\n                               \"Late Malabarba\"))))\n#'user/new-map\nuser\u003e (:surname my-map)\n\"Malabarba\"\nuser\u003e (:delayed-surname my-map)\nResolved\n\"Late Malabarba\"\n#+END_SRC\n\n** The [[http://malabarba.github.io/lazy-map-clojure/lazy-map.iop.html#var-extend-lazy-map][to-lazy-map]] protocol\n\nThis protocol allows you to convert any java class into a lazy map,\nwhere each entry correponds to a method call. Since everything is\nlazy, you can rest assured the methods won’t actually be called until\nyou use them.\n\n#+BEGIN_SRC clojure\nuser\u003e (use 'lazy-map.iop)\nnil\nuser\u003e (extend-lazy-map String)\nnil\n\nuser\u003e (to-lazy-map \"My Own Map!\")\n{:to-char-array #object[clojure.lang.Delay 0x5c3c775a {:status :pending, :val nil}],\n :empty?        #object[clojure.lang.Delay 0x774f63f2 {:status :pending, :val nil}],\n :to-string     #object[clojure.lang.Delay 0x4a62ed8c {:status :pending, :val nil}],\n :intern        #object[clojure.lang.Delay 0x4ddc7018 {:status :pending, :val nil}],\n :chars         #object[clojure.lang.Delay 0x72e5585e {:status :pending, :val nil}],\n :class         #object[clojure.lang.Delay 0x7e39e503 {:status :pending, :val nil}],\n :length        #object[clojure.lang.Delay 0x236a69c5 {:status :pending, :val nil}],\n :trim          #object[clojure.lang.Delay 0xd988100 {:status :pending, :val nil}],\n :bytes         #object[clojure.lang.Delay 0x55671f45 {:status :pending, :val nil}],\n :code-points   #object[clojure.lang.Delay 0x64c7f917 {:status :pending, :val nil}],\n :to-lower-case #object[clojure.lang.Delay 0x1493800b {:status :pending, :val nil}],\n :hash-code     #object[clojure.lang.Delay 0x5d4a8318 {:status :pending, :val nil}],\n :object        #object[clojure.lang.Delay 0x30ba32c3 {:status :pending, :val nil}],\n :to-upper-case #object[clojure.lang.Delay 0x6b6e6a82 {:status :pending, :val nil}]}\n\nuser\u003e (:to-upper-case *1)\n\"MY OWN MAP!\"\n#+END_SRC\n\nNote how there’s an entry for each method. Obviously, only methods\nthat takes no arguments (0-arity) are included.\n\nThere’s also an extra ~:object~ entry holding the string itself.\n\n** License\n\nCopyright © 2015 Artur Malabarba\n\nDistributed under the Eclipse Public License either version 1.0 or (at\nyour option) any later version.\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2FMalabarba%2Flazy-map-clojure","html_url":"https://awesome.ecosyste.ms/projects/github.com%2FMalabarba%2Flazy-map-clojure","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2FMalabarba%2Flazy-map-clojure/lists"}