From type/IO/Path

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method move(IO::Path:D: IO() $to, :$createonly --> Bool:D)
sub    move(IO() $from, IO() $to, :$createonly --> Bool:D)

Copies a file and then removes the original. If removal fails, it's possible to end up with two copies of the file. Returns True on success; fail with X::IO::Move if :$createonly is True and the $to path already exists or if the operation failed for some other reason, such as when $to and $from are the same file.

To avoid copying, you can use rename, if the files are on the same storage device. It also works with directories, while move does not.