4 ms·

I welcome the functional features, but I have to agree that these specific examples are ugly compared to the more familiar alternatives. Maybe this will look m

by BFay 12y ago

I welcome the functional features, but I have to agree that these specific examples are ugly compared to the more familiar alternatives. Maybe this will look more readable after getting used to it, but I'd much rather be looking at Clojure or Scala for now.

bollockitis 12y ago
Out of curiosity, could you share an example of how this compares to Clojure or Scala? I am not familiar with either.
- markc 12y ago
  Here's a quick version in Clojure. I'm sure it can be done cleaner than this.. (def articles [{:title "title1" :author "author1" :tags #{:Java :t2 :t3}} {:title "title2" :author "author1" :tags #{:Jvxa :t2 :t3}} {:title "title3" :author "author3" :tags #{:Java :t3}}]) ;; find the first article in the collection that has the tag “Java”. (first (filter #(contains? (:tags %) :Java) articles)) ;; ==> {:tags #{:t2 :Java :t3}, :title "title1", :author "author1"} ;;get all the elements that match instead of just the first (filter #(contains? (:tags %) :Java) articles) ;; ==> ({:tags #{:t2 :Java :t3}, :title "title1", :author "author1"} {:tags #{:Java :t3}, :title "title3", :author "author3"}) ;;group all the articles based on the author. (group-by :author articles) ;; cheating? ;; ==> {"author1" [{:tags #{:t2 :Java :t3}, :title "title1", :author "author1"} {:tags #{:Jvxa :t2 :t3}, :title "title2", :author "author1"}], "author3" [{:tags #{:Java :t3}, :title "title3", :author "author3"}]} ;;find all the different tags used in the collections (apply clojure.set/union (map :tags articles)) ;; ==> #{:Jvxa :t2 :Java :t3}
  - codygman 12y ago
    (group-by :author articles) groupBy ((==) `on` author) articles What's wrong with cheating? :P
- codygman 12y ago
  formatted Scala code by hibikir from above in thread[0]: def topJavaArticle(articles:List[Article]) = articles.find(_.tags.contains("Java")) def javaArticles(articles:List[Article]) = articles.filter(_.tags.contains("Java")) def byAuthor(articles:List[Article) = articles.groupBy(_.author) 0: https://news.ycombinator.com/item?id=8874785 https://news.ycombinator.com/item?id=8874785
- codygman 12y ago
  I linked a Haskell version above as well: https://news.ycombinator.com/item?id=8878421 https://news.ycombinator.com/item?id=8878421

by BFay 12y ago

bollockitis 12y ago

Out of curiosity, could you share an example of how this compares to Clojure or Scala? I am not familiar with either.

markc 12y ago
Here's a quick version in Clojure. I'm sure it can be done cleaner than this.. (def articles [{:title "title1" :author "author1" :tags #{:Java :t2 :t3}} {:title "title2" :author "author1" :tags #{:Jvxa :t2 :t3}} {:title "title3" :author "author3" :tags #{:Java :t3}}]) ;; find the first article in the collection that has the tag “Java”. (first (filter #(contains? (:tags %) :Java) articles)) ;; ==> {:tags #{:t2 :Java :t3}, :title "title1", :author "author1"} ;;get all the elements that match instead of just the first (filter #(contains? (:tags %) :Java) articles) ;; ==> ({:tags #{:t2 :Java :t3}, :title "title1", :author "author1"} {:tags #{:Java :t3}, :title "title3", :author "author3"}) ;;group all the articles based on the author. (group-by :author articles) ;; cheating? ;; ==> {"author1" [{:tags #{:t2 :Java :t3}, :title "title1", :author "author1"} {:tags #{:Jvxa :t2 :t3}, :title "title2", :author "author1"}], "author3" [{:tags #{:Java :t3}, :title "title3", :author "author3"}]} ;;find all the different tags used in the collections (apply clojure.set/union (map :tags articles)) ;; ==> #{:Jvxa :t2 :Java :t3}
- codygman 12y ago
  (group-by :author articles) groupBy ((==) `on` author) articles What's wrong with cheating? :P
codygman 12y ago
formatted Scala code by hibikir from above in thread[0]: def topJavaArticle(articles:List[Article]) = articles.find(_.tags.contains("Java")) def javaArticles(articles:List[Article]) = articles.filter(_.tags.contains("Java")) def byAuthor(articles:List[Article) = articles.groupBy(_.author) 0: https://news.ycombinator.com/item?id=8874785 https://news.ycombinator.com/item?id=8874785
codygman 12y ago
I linked a Haskell version above as well: https://news.ycombinator.com/item?id=8878421 https://news.ycombinator.com/item?id=8878421