How would I specify the value for a field if another field has a value, but otherwise allow the custom list to be used?
You should be able to do something with a custom list + a formula.
For the formula, if you’re checking for a particular value it would look something like this:
if another_field == ‘something’ then <specified value> else this end
the “else this” would pass the value picked for the custom list.
OK, is there a mockaroo/ruby function to identify if a particular sub-string was generated in a field created via regular expression?
For a simple substring you can use:
my_field.include?("foo")
or to use a regex:
my_field.match(/foo/)