Comment by explainplease

> If I'm looking for option "-e" of the test command, why can't I do...

https://gist.github.com/alphapapa/3cba3ff196147ad42bac#file-...

    $ man test -e

           STRING1 != STRING2
                  the strings are not equal

           INTEGER1 -eq INTEGER2
                  INTEGER1 is equal to INTEGER2

           INTEGER1 -ge INTEGER2
                  INTEGER1 is greater than or equal to INTEGER2
    --

           INTEGER1 -ne INTEGER2
                  INTEGER1 is not equal to INTEGER2

           FILE1 -ef FILE2
                  FILE1 and FILE2 have the same device and inode numbers

           FILE1 -nt FILE2
                  FILE1 is newer (modification date) than FILE2
    --

           -d FILE
                  FILE exists and is a directory

           -e FILE
                  FILE exists

           -f FILE
                  FILE exists and is a regular file