you can use any editor you like. could be vi, vim, nvim, emacs. the point is that your editor receives text from stdin, and writes changes to stdout, in the middle of a pipeline.
hopefully the examples in the readme make sense but maybe not?
hopefully the examples in the readme make sense but maybe not?
beginning of pipeline > output.txt; <editor of choice> output.txt; cat output.txt | rest of pipeline commands
sed, stream editor, takes text from standard in and writes changes to standard out in the middle of a pipeline. sed does this without all the extra overhead a standard editor incurs.
More flexibility with awk, but also more overhead than sed, but less than vim.
With a bit of macro magic and/or readning from/writing out to named pipe, can do the same interactively with vim.