I see the same thing, but I think it's supposed to be a rightward arrow, as in a function from positive numbers to negative numbers. At least, that's how it usually appears in the Racket documentation.
Other people have taken that approach, for example the HALO project in Haskell. But the imprecision of the defunctionalizaton often makes it hard to prove the properties you want, especially without static types.
[+] [-] auggierose|10 years ago|reply
[+] [-] groovy2shoes|10 years ago|reply
[+] [-] samth|10 years ago|reply
[+] [-] spdegabrielle|10 years ago|reply
Does this mean I can verify C++, Haskell, Python, JavaScript & Common Lisp code that uses Higher Order Functions?
[+] [-] samth|10 years ago|reply
[+] [-] quietplatypus|10 years ago|reply
[+] [-] samth|10 years ago|reply
[+] [-] jsli|10 years ago|reply