Is there a dry run mode before the replacement takes place?

[yangchenyun]

It would be scary if the some matches go wrong.

[harthur]

--preview or -p to do a dry run. I might change it to show the possible replacements then prompt whether to perform them, what do you think about that?

[yangchenyun]

You mean start a repl when run the command, and let the user choose to commit the replacement or not?
That would be awesome, like the git interactive add mode. 👍
But I think it deserves a separate switch such as --interactive or -i as the -p mode is still useful for a quick scan.

[harthur]

Thanks, I want to do an interactive mode like you were describing, but I was thinking in the meantime at least show all the potential changes at once (like it does now), and ask "do you want to make these changes? [y]n" every time to at least prevent mishaps (I've forgotten the -p flag myself before).

[yangchenyun]

I think this is useful, but every time seems a bit annoying especially for simple changes.
And as similar programs all have the direct or dry-run mode, so I think it should be user (such as myself)'s responsible to get it right.