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by tel 4640 days ago
Typeable is interesting in theory and generic traversals are a godsend, but usually I find that when I'm reaching for that particular hammer I should check twice.
1 comments
brandonbloom 4640 days ago
I'll agree it's best to avoid fully open unions when you can, but some (super useful) things truly don't work that way. Check out http://okmij.org/ftp/Computation/monads.html#ExtensibleDS for a cool example.
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tel 4640 days ago
I always think of Control.Exception as the poster child for open unions.
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brandonbloom 4640 days ago
Perfect, since exceptions are a subset of effects! Check out http://math.andrej.com/eff/ and its literature.
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