# If you'd like to omit non-matching lines from the result; add ';d' to the end of the expression.
sed -E 's/(.*)/$1,$1,$1/gm;t' <<< "HIT & REPLACE
11/21/1994
12/11/2014
03/31/2016 # Hit only if unchecked for length months/days
NO-HIT
11//12/2090
37/14/2015
20/27/2011
10/32/1964
14/03/2020
HINTS
- Use g-flag only.
"
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for SED, please visit: https://www.gnu.org/software/sed/manual/html_node/The-_0022s_0022-Command.html