remove comments (even those starting with spaces), empty lines (even those containing spaces) in one grep command

grep -vE '^\s*(#|$)' textfile
useful for discarding even those comments which start with blanks or those empty lines which contain blanks
Sample Output
[root@docker ~]# grep -vE '^\s*(#|$)' /etc/nsswitch.conf
passwd:     files sss
shadow:     files sss
group:      files sss
hosts:      files dns myhostname
bootparams: nisplus [NOTFOUND=return] files
ethers:     files
netmasks:   files
networks:   files
protocols:  files
rpc:        files
services:   files sss
netgroup:   nisplus sss
publickey:  nisplus
automount:  files nisplus sss
aliases:    files nisplus

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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