[Haskell-cafe] What's this pattern called?
Martijn van Steenbergen
martijn at van.steenbergen.nl
Thu Oct 22 03:47:32 EDT 2009
> data ExprF r
> = Add r r
> | Sub r r
> | Mul r r
> | Div r r
> | Num Int
This is a well-known pattern that for example allows nice notation of
morphisms. But what is it called? I've heard fixed-point view, open
datatypes and some others, but I'm curious where this pattern comes up
in literature and what it is called there.
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