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# Algorithm ℳ
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During the implementation of my library "Aasam", based on the paper "Precedences in specifications and implementations of programming languages" by Annika Aasa, was the first time I fully read and understood an academic CS paper. It's a nice algorithm, and worth revisiting.
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If you want to look at the implementation ahead-of-time, [Hackage](https://hackage.haskell.org/package/aasam) has got you covered. Frankly though, just keep reading; it was also the first time I wrote a Haskell program, and the code not terribly penetrable.
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## Distfix Grammars
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_Distfix grammars and notation are more commonly referred to as "mixfix", but the paper calls them "distfix" and that's what I'm sticking with._
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The idea of distfix grammars is to provide a formalism for manipulating user-defined operators. The formalism is weaker than that of context-free grammars--- CFGs can describe far more languages then DFGs--- but it is because of this weakness that we can reason about DFGs with relative ease.
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Let's look at a definition.
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*STUFF HERE*
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As we can see, ... |