Pieces of Yesod: Inverting a Haskell Function

I’ve recently been working with web frameworks, and decided to have a play with what Haskell has to offer for web resources. One of the several frameworks available is Yesod. Web frameworks need some sort of mapping between URLs and internal logic, usually called routing. In Yesod, routing is done with a “pieces” mechanism. You [...]Image may be NSFW.
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