Safe Haskell | None |
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Language | Haskell2010 |
A pseudo derivation. Derive a (non-recursive) fold function for the type which takes one function per alternative constructor. Each function takes the same arguments as the constructor and returns a value. When applied to a value the fold function applies the function for the matching constructor to the constructor fields. This provides a first-class alternative to pattern matching to deconstruct the data type.