Currently the default value filter only works with strings, but it should be able to work with all primitives, dates and durations at least. Then, when it deals with e.g. a date it can apply some default parsing to make it a proper date value; e.g. support timestamps or strtotime().
Besides those data types, of course support for upcasting entities by ID or so would be nice also, but that's another issue imho. (Typed data shouldn't special case entities).
Active
2.1
Data filters
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