RRF

RRF is short for Reverse-ReverseFuck and it uses the commands of ReverseFuck but the program is written backwards. Every valid Brainfuck program is a valid RRF program but a different function. You can also write program that is the same function in Brainfuck as RRF (a polyglot program): ,[.,]. and +[,[.,]][[.,].]-

You can also do another variation PRRF (Palindrome-Reverse-ReverseFuck) that requires you to write half of the program (the second half) and it writes the rest itself, just like the programs above are, so you would write: ,]. and [[.,].]-