This directory contains the "remains" of the old parameter setting infrastructure used by Z3. Old code (mostly `smt::context`) is still based on the front_end_params structure. However, we removed support for the old INI file infrastructure. Instead, we have functions for setting the fields of front_end_params using parameter sets (params_ref). Moreover, many of the parameters in front_end_params are now "hidden". That is, they can't be set from the command line or using the command `set-option`.