$ sudo pacman -U gimp-print-lprng-4.2.7-2-x86_64.pkg.tar.gz
Password:
loading package data...
checking dependencies...
error: replacing packages with -U is not supported yet
error: you can replace packages manually using -Rd and -U
error: failed to prepare transaction (conflicting dependencies)
:: gimp-print-lprng: conflicts with cups
:: gimp-print-lprng: conflicts with ghostscript