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I didn't know that. This implementation is much more convenient and powerful than TextWrangler's.
Thanks for your prompt support,
Sorry for not stating my idea clearly.
Add and Remove Prefix or Suffix: These actions will prepend or append the supplied string to each line processed (or remove same).

This is how TextWrangler did it:

01. Select multi-line texts you want to add prefix/suffix, choose Prefix/Suffix Lines... from menu

02. Enter prefix and/or suffix values you want in the dialog

03. You have prefix/suffixed added to each lines
04. Now you want to remove suffix. Choose Prefix/Suffix Lines... from menu, then enter suffix value to be removed

05. If lines have same entered suffix, it will be removed as below