Apologies - I've noticed some mistakes corrected as follows:
Brian Hulley wrote:
class //x a b where
x : a -> b
class //FooCon a b where
FooCon : a -> b
class //x a b | a -> b where -- I think this fundep is
correct
x :: a->b -- I can never get used
to having to write :: instead of :
class //FooCon a b | b -> a where
FooCon :: a->b
This is a lot more powerful than just OOP, because we could have
different views of a data type, selecting out those components which
are relevant to particular operations:
data Element = TerminalPunct | TerminalValue | NonTerminal |
Push | Pop
data Action = Push | Pop
data Insertion = TerminalValue | NonTerminal | Push
without having to artificially construct various injections...
No - these are not in fact views. A view would be given by multiple
predicates eg (//Push a,//Pop a) => ... a ... as normal.
Regards, Brian.
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