Haskell function in Python FFI

Question

I try to use haskell function in my Python program using FFI.

My function is like f :: String -> String

anyone can help me?

i have another function f2 :: [(Double,Double,Double)] -> ((Double,Double,Double),(Double,Double,Double))

edit:

i found some information here: https://github.com/nh2/call-haskell-from-anything

i know how to call function like fib :: Int -> Int in Python

ex.

module Example where

import Foreign.C.Types

fibonacci :: Int -> Int
fibonacci n = fibs !! n
    where fibs = 0 : 1 : zipWith (+) fibs (tail fibs)

fibonacci_hs :: CInt -> CInt
fibonacci_hs = fromIntegral . fibonacci . fromIntegral

foreign export ccall fibonacci_hs :: CInt -> CInt

but i don't know how to make funciton :: String -> String callable in Python

A first step is to change the list into a contiguous data type such as Vector Double and pass a pointer and length. — gspr
@gspr: I think the library that OP is using works on a slightly higher level of abstraction, so that a list is probably easier to handle — Niklas B.
Some of these functions might be helpful: haskell.org/ghc/docs/latest/html/libraries/base/… — Neil Forrester

sclv sclv · Accepted Answer · 2013-03-01T14:59:41

Just as you need to wrap your fib function on Int to a function on CInt, you similarly need to wrap your function on String as a function on CString: http://www.haskell.org/ghc/docs/latest/html/libraries/base/Foreign-C-String.html

Haskell function in Python FFI

2 Answers