bash function to highlight non-printing characters: tab, newline, BOM, nbsp

hl-nonprinting () { local C=$(printf '\033[0;36m') B=$(printf '\033[0;46m') R=$(printf '\033[0m') np=$(env printf "\u00A0\uFEFF"); sed -e "s/\t/${C}▹&$R/g" -e "s/$/${C}⁋$R/" -e "s/[$np]/${B}& $R/g";}
Can't see it here, but the non-breaking space is highlighted :) Of course, cat -t -e achieves something similar, but less colourful. Could add more code points from https://en.wikipedia.org/wiki/Space_%28punctuation%29#Spaces_in_Unicode
Sample Output
$ env printf '\uFEFFfoo\u00A0bar\nfie\tfum'|hl-nonprinting 
 foo? bar⁋
fie▹    fum⁋

-1
By: unhammer
2012-11-07 10:09:40

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What Others Think

ugh, commandlinefu shows ▹ and ⁋ as the html entity :/
unhammer · 289 weeks and 3 days ago

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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