If I understand correctly, custom fields work like this:
key(string/int) => value(string/int)
Is it possible to define a custom field like this?
key(string/int) => value(array (string/int, string/int))
I want to use such a structure for storing a series of quotations in [quote, source] format, thinking that it would minimize potential input error compared with, say, str_splitting a single value.
Yes you can, either by code:
Or simply using the custom fields UI, add ass many values as you want one at a time and make sure they all have the same meta_key.