There seem to be lots of papers discussing the functional programming paradigm terminology for Haskell, such as monad, category theory, lambda calculus, *morphism, etc. People study concepts and theory derived from haskell in depth.
Is there any programming language theory (PLT) research on the Mathematica paradigm (such as rule-based system, term-rewriting, and other mechanisms MMA uses)? How do contemporary PLT-ers think about Mathematica?
It seems that they often omit Mathematica to some degree. Honestly, I don't know much about Haskell, but I also can't imagine that Mathematica is completely missing some crucial aspect of programming theory that makes it that much inferior.
Also, if the truth is "no, there aren't!, MMA is fine and perfect!", then why aren't there as many papers as for Haskell talking about the Mathematica programming language?