LexiFi, a financial software company, writes about OCaml internals and a contract description language for modelling financial derivatives.
HN links it for its algebraic description of financial contracts and its OCaml posts, such as unboxed floats, which commenters cite as explanations.
This seems like a legitimate use-case for permissioned ledgers where various lenders have necessarily siloed lending history data but also have an interest in seeing what data everyone else has for prospective lendees.
In the longer run, you can imagine not just credit history data being exchanged (with the permission of the borrower perhaps) but also the ability to trade the loan products themselves, most of which is done OTC right now. Fixed income contracts can be described as "smart contracts" [1]
[1] https://lexifi.com/files/resources/MLFiPaper.pdf
Well I love python, but this reminds me of a set of an old paper by Peyton-Jones of GHC fame, which developed a Haskell combinator lib that did something like this. I'm sure the state of the art has left this system long behind, but it's a pretty interesting concept.
Composing contracts: an adventure in financial engineering, Simon Peyton Jones, Jean-Marc Eber, Julian Seward. ICFP, 2000
http://www.lexifi.com/downloads/MLFiPaper.pdf
See also:
http://homepages.inf.ed.ac.uk/wadler/realworld/lexifi.html
FpML (Financial Products Markup Language) was conceived shortly before the paper referenced in the blog post.[1]
One of the paper's authors went on to create MLFi, a modelling language for finance[2]
This stuff is a bit esoteric but I think it will attract more attention because of its relevance to smart contracts.
1: http://www.fpml.org/
2: https://www.lexifi.com/product/technology/contract-description-language
For those who like me aren't familiar with the concept of "float boxing", I think this is the same thing: https://www.lexifi.com/ocaml/unboxed-floats-ocaml/
Basically if I understand correctly this removes an indirection when using floats, probably reducing the memory footprint and improving performance.
> I'd love to see an example of such a restricted contract language.
A Formal Language for Analyzing Contracts, http://szabo.best.vwh.net/contractlanguage.html
Composing contracts:
an adventure in nancial engineering, https://lexifi.com/files/resources/MLFiPaper.pdf
For a good counter counter example to this guy's rant:
Functional Payout Framework used for exotic options pricing at Barclays Capital, developed entirely in Haskell: http://www.lexifi.com/downloads/frankau.pdf