ruby - How to make private and public user's fields in rails? -

i want give public , private options fields user. suppose, want make private "birth date" field, should not appeared on detail page other user.

i have customized registration controller in devise. fields saving ,updating , showing don't know how hide private fields other users. confused how start????

if have method e.g. current_user (current logged in user, if use e.g. devise) can like

<%= @user.birth_date if @user == current_user %>