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Trouble understanding Danvy's functional unparsing

I've read Danvy's paper here[1], and I fail to understand why CPS is necessary for the types to work out. I've written a basic version of "functional sprintf" in OCaml that doesn't use CPS and seems to typecheck fine:


let int_ s i = s ^ string_of_int i

let float_ s i = s ^ string_of_float i

let (@) f g s a b = g (f s a) b

let sprintf fmt = fmt ""

let (_s : string) =
let x = sprintf (int_ @ float_) 1 1.0 in
let y = sprintf (int_ @ float_ @ int_) 1 1.0 2 in
x ^ y

[1]: http://www.brics.dk/RS/98/12/BRICS-RS-98-12.pdf

By jezng at 2015-05-18 05:31 | LtU Forum | 7 comments | other blogs | 4011 reads