what's going on with this dash '-' thing?












3















I was trying to export the python environment requirements and this is what I intended to do:



conda list -e > requirements.txt


However I mistakendly typed this instead:



conda list -e -> requirements.txt


It still works but the file is having fewer lines in the content. I want to know what exactly happend. I searched but couldn't find an explaination on the - in this case. Thanks!










share|improve this question



























    3















    I was trying to export the python environment requirements and this is what I intended to do:



    conda list -e > requirements.txt


    However I mistakendly typed this instead:



    conda list -e -> requirements.txt


    It still works but the file is having fewer lines in the content. I want to know what exactly happend. I searched but couldn't find an explaination on the - in this case. Thanks!










    share|improve this question

























      3












      3








      3








      I was trying to export the python environment requirements and this is what I intended to do:



      conda list -e > requirements.txt


      However I mistakendly typed this instead:



      conda list -e -> requirements.txt


      It still works but the file is having fewer lines in the content. I want to know what exactly happend. I searched but couldn't find an explaination on the - in this case. Thanks!










      share|improve this question














      I was trying to export the python environment requirements and this is what I intended to do:



      conda list -e > requirements.txt


      However I mistakendly typed this instead:



      conda list -e -> requirements.txt


      It still works but the file is having fewer lines in the content. I want to know what exactly happend. I searched but couldn't find an explaination on the - in this case. Thanks!







      linux io-redirection arguments output dash






      share|improve this question













      share|improve this question











      share|improve this question




      share|improve this question










      asked 3 hours ago









      user3768495user3768495

      1473




      1473






















          1 Answer
          1






          active

          oldest

          votes


















          5














          The -e option doesn't take any argument after it, so the - is just a regular argument to list. The first and only positional argument conda list has is a regular expression, which causes it to




          List only packages matching this regular expression.




          In your case, it will have listed only packages matching - (so, containing a hyphen in their name). That output was then redirected into requirements.txt as you intended. It will be shorter than conda list -e's output because there are some non-matching packages that aren't included.






          share|improve this answer























            Your Answer








            StackExchange.ready(function() {
            var channelOptions = {
            tags: "".split(" "),
            id: "106"
            };
            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: false,
            noModals: true,
            showLowRepImageUploadWarning: true,
            reputationToPostImages: null,
            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%2funix.stackexchange.com%2fquestions%2f498034%2fwhats-going-on-with-this-dash-thing%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









            5














            The -e option doesn't take any argument after it, so the - is just a regular argument to list. The first and only positional argument conda list has is a regular expression, which causes it to




            List only packages matching this regular expression.




            In your case, it will have listed only packages matching - (so, containing a hyphen in their name). That output was then redirected into requirements.txt as you intended. It will be shorter than conda list -e's output because there are some non-matching packages that aren't included.






            share|improve this answer




























              5














              The -e option doesn't take any argument after it, so the - is just a regular argument to list. The first and only positional argument conda list has is a regular expression, which causes it to




              List only packages matching this regular expression.




              In your case, it will have listed only packages matching - (so, containing a hyphen in their name). That output was then redirected into requirements.txt as you intended. It will be shorter than conda list -e's output because there are some non-matching packages that aren't included.






              share|improve this answer


























                5












                5








                5







                The -e option doesn't take any argument after it, so the - is just a regular argument to list. The first and only positional argument conda list has is a regular expression, which causes it to




                List only packages matching this regular expression.




                In your case, it will have listed only packages matching - (so, containing a hyphen in their name). That output was then redirected into requirements.txt as you intended. It will be shorter than conda list -e's output because there are some non-matching packages that aren't included.






                share|improve this answer













                The -e option doesn't take any argument after it, so the - is just a regular argument to list. The first and only positional argument conda list has is a regular expression, which causes it to




                List only packages matching this regular expression.




                In your case, it will have listed only packages matching - (so, containing a hyphen in their name). That output was then redirected into requirements.txt as you intended. It will be shorter than conda list -e's output because there are some non-matching packages that aren't included.







                share|improve this answer












                share|improve this answer



                share|improve this answer










                answered 3 hours ago









                Michael HomerMichael Homer

                47.6k8124163




                47.6k8124163






























                    draft saved

                    draft discarded




















































                    Thanks for contributing an answer to Unix & Linux Stack Exchange!


                    • 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%2funix.stackexchange.com%2fquestions%2f498034%2fwhats-going-on-with-this-dash-thing%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

                    Сан-Квентин

                    Алькесар

                    Josef Freinademetz