I think this is impossible. However, is it possible to change a field into fields on Drupal 7? I have a content type of author. We used the "Title" field for user full name with their title. Is it possible to change it to "First Name", "Middle Name", "Last Name", and "Title" fields?
It's definitely possible, but will require some coding. I can't work out the whole thing for you but I can point you in a direction.
You would have to create three new fields for 'first name', 'last name' and 'title' in the content type.
Then create a script that loads all of the nodes of that type with node_load_multiple then iterates through them, taking the old value of 'title' and splitting it using regex or the php 'explode' string function. Then using entity_metadata_wrapper, stick the individual values into the new fields and save the node.
Using drush, you can run the script like this: drush php-script scriptname.php
You might use Field Collection. It provides fieldable entities that, themselves, can be added to other fieldable entities.
There's no way to do this without some coding, as far as I can see. Work with the following assumptions:You know that there is always 3 or 4 elements, and in the case where there is 3 elements, the missing element is always the middle name. So load the node, get the value of the old field, explode it into an array, count the number of elements and if it's 3, then insert an empty element at array. Then you have an array with 0 => First, 1 => Middle, 2 => Last, 3 => Title. Now use entity_metadata_wrapper to insert the individual array elements into the new fields. 0 into First Name, 1 into Middle Name (regardless of if it's empty or not), 2 into Last Name, and 3 into Title. Once you have the new fields populated, delete the old field from the content type, and use display rules or theming to decide when to display the Middle Name field, based on whether or not it has content. Something like that should work.