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












2















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



























    2















    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

























      2












      2








      2








      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














      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




      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

      1423




      1423






















          1 Answer
          1






          active

          oldest

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          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























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            1 Answer
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            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






























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