Concatenate to a list of string another string












0















The below code gives back a list of String but I want it work on multiple cases. The problem is that I can't create the same exact result with recursion.
The program gives back the following result:



replaceTabs 6 ["thello world"]

=> [" hello world"]


Now this should work with a longer list like:



replaceTabs 6 ["asd dsa","thello world"]

=> ["asd dsa"," hello world"]


Simple concat doesn't work, because it will give back undefined pattern.



replaceTab' :: Int -> [[Char]] -> [Char]
replaceTab' n [[x]] =
if x == 't' then replicate n ' '
else [x]

replaceTabs :: Int -> [String]-> [String]
replaceTabs n [""] = [""]
replaceTabs n (x:xs) = (return . concat $ [replaceTab' n [a] | a <- (map (:) (x))])









share|improve this question



























    0















    The below code gives back a list of String but I want it work on multiple cases. The problem is that I can't create the same exact result with recursion.
    The program gives back the following result:



    replaceTabs 6 ["thello world"]

    => [" hello world"]


    Now this should work with a longer list like:



    replaceTabs 6 ["asd dsa","thello world"]

    => ["asd dsa"," hello world"]


    Simple concat doesn't work, because it will give back undefined pattern.



    replaceTab' :: Int -> [[Char]] -> [Char]
    replaceTab' n [[x]] =
    if x == 't' then replicate n ' '
    else [x]

    replaceTabs :: Int -> [String]-> [String]
    replaceTabs n [""] = [""]
    replaceTabs n (x:xs) = (return . concat $ [replaceTab' n [a] | a <- (map (:) (x))])









    share|improve this question

























      0












      0








      0








      The below code gives back a list of String but I want it work on multiple cases. The problem is that I can't create the same exact result with recursion.
      The program gives back the following result:



      replaceTabs 6 ["thello world"]

      => [" hello world"]


      Now this should work with a longer list like:



      replaceTabs 6 ["asd dsa","thello world"]

      => ["asd dsa"," hello world"]


      Simple concat doesn't work, because it will give back undefined pattern.



      replaceTab' :: Int -> [[Char]] -> [Char]
      replaceTab' n [[x]] =
      if x == 't' then replicate n ' '
      else [x]

      replaceTabs :: Int -> [String]-> [String]
      replaceTabs n [""] = [""]
      replaceTabs n (x:xs) = (return . concat $ [replaceTab' n [a] | a <- (map (:) (x))])









      share|improve this question














      The below code gives back a list of String but I want it work on multiple cases. The problem is that I can't create the same exact result with recursion.
      The program gives back the following result:



      replaceTabs 6 ["thello world"]

      => [" hello world"]


      Now this should work with a longer list like:



      replaceTabs 6 ["asd dsa","thello world"]

      => ["asd dsa"," hello world"]


      Simple concat doesn't work, because it will give back undefined pattern.



      replaceTab' :: Int -> [[Char]] -> [Char]
      replaceTab' n [[x]] =
      if x == 't' then replicate n ' '
      else [x]

      replaceTabs :: Int -> [String]-> [String]
      replaceTabs n [""] = [""]
      replaceTabs n (x:xs) = (return . concat $ [replaceTab' n [a] | a <- (map (:) (x))])






      string list haskell concat






      share|improve this question













      share|improve this question











      share|improve this question




      share|improve this question










      asked Nov 24 '18 at 17:30









      Akos FajsziAkos Fajszi

      445




      445
























          1 Answer
          1






          active

          oldest

          votes


















          3














          This



          replaceTab' :: Int -> [[Char]] -> [Char]


          is the same as,



          replaceTab' :: Int -> [String] -> String


          What you should focus on is implementing a function,



          replaceTab :: Int -> String -> String


          which "fixes" a single String. Then replaceTabs is simply,



          replaceTabs :: Int -> [String] -> [String]
          replaceTabs n = map (replaceTab n)





          share|improve this answer























            Your Answer






            StackExchange.ifUsing("editor", function () {
            StackExchange.using("externalEditor", function () {
            StackExchange.using("snippets", function () {
            StackExchange.snippets.init();
            });
            });
            }, "code-snippets");

            StackExchange.ready(function() {
            var channelOptions = {
            tags: "".split(" "),
            id: "1"
            };
            initTagRenderer("".split(" "), "".split(" "), channelOptions);

            StackExchange.using("externalEditor", function() {
            // Have to fire editor after snippets, if snippets enabled
            if (StackExchange.settings.snippets.snippetsEnabled) {
            StackExchange.using("snippets", function() {
            createEditor();
            });
            }
            else {
            createEditor();
            }
            });

            function createEditor() {
            StackExchange.prepareEditor({
            heartbeatType: 'answer',
            autoActivateHeartbeat: false,
            convertImagesToLinks: true,
            noModals: true,
            showLowRepImageUploadWarning: true,
            reputationToPostImages: 10,
            bindNavPrevention: true,
            postfix: "",
            imageUploader: {
            brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
            contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
            allowUrls: true
            },
            onDemand: true,
            discardSelector: ".discard-answer"
            ,immediatelyShowMarkdownHelp:true
            });


            }
            });














            draft saved

            draft discarded


















            StackExchange.ready(
            function () {
            StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53460700%2fconcatenate-to-a-list-of-string-another-string%23new-answer', 'question_page');
            }
            );

            Post as a guest















            Required, but never shown

























            1 Answer
            1






            active

            oldest

            votes








            1 Answer
            1






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes









            3














            This



            replaceTab' :: Int -> [[Char]] -> [Char]


            is the same as,



            replaceTab' :: Int -> [String] -> String


            What you should focus on is implementing a function,



            replaceTab :: Int -> String -> String


            which "fixes" a single String. Then replaceTabs is simply,



            replaceTabs :: Int -> [String] -> [String]
            replaceTabs n = map (replaceTab n)





            share|improve this answer




























              3














              This



              replaceTab' :: Int -> [[Char]] -> [Char]


              is the same as,



              replaceTab' :: Int -> [String] -> String


              What you should focus on is implementing a function,



              replaceTab :: Int -> String -> String


              which "fixes" a single String. Then replaceTabs is simply,



              replaceTabs :: Int -> [String] -> [String]
              replaceTabs n = map (replaceTab n)





              share|improve this answer


























                3












                3








                3







                This



                replaceTab' :: Int -> [[Char]] -> [Char]


                is the same as,



                replaceTab' :: Int -> [String] -> String


                What you should focus on is implementing a function,



                replaceTab :: Int -> String -> String


                which "fixes" a single String. Then replaceTabs is simply,



                replaceTabs :: Int -> [String] -> [String]
                replaceTabs n = map (replaceTab n)





                share|improve this answer













                This



                replaceTab' :: Int -> [[Char]] -> [Char]


                is the same as,



                replaceTab' :: Int -> [String] -> String


                What you should focus on is implementing a function,



                replaceTab :: Int -> String -> String


                which "fixes" a single String. Then replaceTabs is simply,



                replaceTabs :: Int -> [String] -> [String]
                replaceTabs n = map (replaceTab n)






                share|improve this answer












                share|improve this answer



                share|improve this answer










                answered Nov 24 '18 at 17:43









                Jorge AdrianoJorge Adriano

                2,220918




                2,220918
































                    draft saved

                    draft discarded




















































                    Thanks for contributing an answer to Stack Overflow!


                    • Please be sure to answer the question. Provide details and share your research!

                    But avoid



                    • Asking for help, clarification, or responding to other answers.

                    • Making statements based on opinion; back them up with references or personal experience.


                    To learn more, see our tips on writing great answers.




                    draft saved


                    draft discarded














                    StackExchange.ready(
                    function () {
                    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53460700%2fconcatenate-to-a-list-of-string-another-string%23new-answer', 'question_page');
                    }
                    );

                    Post as a guest















                    Required, but never shown





















































                    Required, but never shown














                    Required, but never shown












                    Required, but never shown







                    Required, but never shown

































                    Required, but never shown














                    Required, but never shown












                    Required, but never shown







                    Required, but never shown







                    Popular posts from this blog

                    Wiesbaden

                    Marschland

                    Dieringhausen