Use mutate or similar as part of recipes?



Let's say I have a dataset of houses with a last sale date. Some of these are missing because the home never had a last sale date, and so I'd like to set the missing values to a baseline, like say, 1900-01-01. Is this possible using recipes, I don't want to drop or impute these, as that doesn't really make sense for the data.


We're planning on having steps that can do this (hopefully ready for the next release in a few weeks).