What is "monadic reflection"?

Question

What is "monadic reflection"?

How can I use it in F#-program?

Is the meaning of term "reflection" there same as .NET-reflection?

Answer 1

Monadic reflection is essentially a grammar for describing layered monads or monad layering. In Haskell describing also means constructing monads. This is a higher level system so the code looks like functional but the result is monad composition - meaning that without actual monads (which are non-functional) there's nothing real / runnable at the end of the day. Filinski did it originally to try to bring a kind of monad emulation to Scheme but much more to explore theoretical aspects of monads.

Correction from the comment - F# has a Monad equivalent named "Computation Expressions"

Filinski's paper at POPL 2010 - no code but a lot of theory, and of course his original paper from 1994 - Representing Monads. Plus one that has some code: Monad Transformers and Modular Interpreters (1995)

Oh and for people who like code - Filinski's code is on-line. I'll list just one - go one step up and see another 7 and readme. Also just a bit of F# code which claims to be inspired by Filinski

Answer 2

I read through the first Google hit, some slides:

http://www.cs.ioc.ee/mpc-amast06/msfp/filinski-slides.pdf

From this, it looks like

1. This is not the same as .NET reflection. The name seems to refer to turning data into code (and vice-versa, with reification).
2. The code uses standard pure-functional operations, so implementation should be easy in F#. (once you understand it)
3. I have no idea if this would be useful for implementing an immutable cache for a recursive function. It look like you can define mutable operations and convert them to equivalent immutable operations automatically? I don't really understand the slides.

Oleg Kiselyov also has an article, but I didn't even try to read it. There's also a paper from Jonathan Sobel (et al). Hit number 5 is this question, so I stopped looking after that.