The symbolic differentiation of univariate expressions I was reading "Doug McIlroy: McCarthy Presents Lisp" and the phrase "symbolic differentiation of univariate expressions" triggered a faint memory of a demonstration of differentiation done in haskell using higher order functions.  (I think my memory is of using the language to produce a function that is the differential of a function given.)  

However I haven't been able to find any other reference to the above phrase in lisp or ML-based languages.  

Does anyone have more information on this, and is "symbolic differentiation of univariate expressions" the same thing as the memory I described?
You might be looking for automatic differentiation, which is an entire field of research; many techniques are known.