ok some years have passed, but I don't see File::Slurp mentioned here which provide edit_file and edit_file_lines. 
# replace all occurrences in the file
edit_file { s/foo/bar/gs } myfile.txt> 
# replace occurrences a line at a time
edit_file_lines { s/foo/bar/g } myfile.txt>

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that said, I see Tie::File mentioned here which looks like a better solution for my case.

In reply to Re: In place editing of text files by sm@sh
in thread In place editing of text files by jevaly

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