How to find and replace words in a text file?

Question

linux

Hello! Faced such a problem: how to completely replace words in a text file that start the same way but end differently? For example, you need to completely replace several words that begin with "Repeat". Under the replacement should be "Repeat", "Repetition", "Repeat", "Repeat".
How to do it in Sublime Text or some other editor? Or maybe there is a command for Linux?

Answer 1

In any streaming text editor capable of regexps, from sed to a one-liner with "perl -pe"

Answer 2

sed -i~ 's/\(repeat\w*\)/42/gI' <filename>
We use sed to solve the problem. The -i switch means direct editing of the file (in-place). The tilde behind -i is a suffix that will be added to the name of the original file, it will have a backup in case something goes wrong.
Regular:
s - replacement modifier
(repeat\w*) - look for groups starting with "repeat" followed by any number of character/number/underscore. Backslashes are needed to escape parentheses.
42 - what we replace the desired groups with
g - we are looking for all occurrences
I - case-insensitive search