xargs mock run

Often, when user uses bit more complex syntax with xargs (or find -exec, for that matter) the command spectacularly fails, and they dont know why.   It would be beneficial to be able to mock run a command - just print what is to be run, so user knows what exactly is passed to the program, so they could adjust/correct their command to do what they intended. It is specially important when rm(1) is involved, as it can do real damage.   Didnt know how to call it but, you can figure out more accurate, or better name for it.