I would like to have a regular expression that I can use in TextWrangler. I've read that substituting for \n+ will allow me to add the suffix but I do not know how to duplicate and add the separator.
Input:
A
B
C
Output
A_A_suffix
B_B_suffix
C_C_suffix
I cannot confirm about TextWrangler right now since don't have my mac, but you can use this regex which will work on Notepad++ and Sublime:
(.+)
With this replacement string:
$1_$1_suffix