This is a typed way of representing BuiltinData/Data. It is highly encouraged you use PAsData to keep track of what "species" of Data value you actually have. Data can be a Constr (for sum of products - ADTs), Map (for wrapping assoc maps of Data to Data), List (for wrapping builtin lists of data), I (for wrapping builtin integers), and B (for wrapping builtin bytestrings).
Consider a function that takes in and returns a B data value - aka ByteString as a Data value. If you use the direct Plutarch synonym to Data - PData, you'd have:
foo :: Term s (PData :--> PData)That's not very informative - you have no way to ensure that you're actually working with B data values. You could use PAsData instead:
foo :: Term s (PAsData PByteString :--> PAsData PByteString)Now, you have assurance that you're working with a Data value that actually represents a builtin bytestring!
Wrapping and unwrapping to and from PAsData terms is provided by the PIsData typeclass. Specifically, by the functions- pfromData and pdata.
Some useful instances of these functions:
pfromData :: Term s (PAsData PInteger) -> Term s PInteger
pfromData :: Term s (PAsData PByteString) -> Term s PByteString
pfromData :: Term s (PAsData (PBuiltinList (PAsData a))) -> Term s (PBuiltinList (PAsData a))
pdata :: Term s PInteger -> Term s (PAsData PInteger)
pdata :: Term s PByteString -> Term s (PAsData PByteString)
pdata :: Term s (PBuiltinList (PAsData a)) -> Term s (PAsData (PBuiltinList (PAsData a)))