Bash: ls, cat -n, echo: List Filenames of Current Directory

cat_n_ls=$(ls | cat -n) assigns ls | cat -n to a variable. ls lists filenames in the current directory. Which is then passed tocat -n which numbers each line. echo "$cat_n_ls" then displays the result. "$cat_n_ls" has quotation marks to preserve newlines. The script above returns something similar to the following example:

     1 file1.sh
     2 file2.sh
     3 file3.sh
     4 file4.sh
     5 file5.sh
     6 file6.sh
     7 file7.sh