The problem: Given a big, hairy, often-changing Route custom type, and a pair of functions Route -> String and String -> Maybe Route, how can we be sure that (almost) every Route turned into a string and back into Route produces the same value that we started with? Route looks like: module Route …

Extracting type metadata from Elm code?

miniBill September 11, 2020, 6:26am 17

Indeed! The type for variant0 wasn’t general enough!

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