Safe Haskell | Safe-Inferred |
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Default lenses for simple total getters and monomorphic updates. Useful for creating accessor labels for single constructor datatypes. Also useful field labels that are shared between all the constructors of a multi constructor datatypes.
Documentation
:: (f -> o) | Getter. |
-> ((o -> i) -> f -> g) | Modifier. |
-> (f -> g) :-> (o -> i) |
Create a total lens from a getter and a modifier.
We expect the following law to hold:
get l (set l a f) == a
set l (get l f) f == f