The function takes the list of exclusions and transforms them into an expression that is then parsed and evaluated to apply the exclusions to the supplied candidate set using standard subsetting routines.
exclude(candidate_set, exclusions)
A matrix or data frame in the "wide" format containing all permitted combinations of attributes. The default is NULL. If no candidate set is provided, then the full factorial subject to specified exclusions will be used.
A list of exclusions Often this list will be pulled directly from the list of options or it is a modified list of exclusions
A restricted candidate set