Action View Date Helpers
The Date Helper primarily creates select/option tags for different kinds of dates and times or date and time elements. All of the select-type methods share a number of common options that are as follows:
:prefix - overwrites the default prefix of “date” used for the select names. So specifying “birthday” would give birthday[month] instead of date[month] if passed to the select_month method.
:include_blank - set to true if it should be possible to set an empty date.
:discard_type - set to true if you want to discard the type part of the select name. If set to true, the select_month method would use simply “date” (which can be overwritten using :prefix) instead of date[month].