[Haskell-cafe] best way to deal with #defines when developing ffi's

[John Millikin]

When using c2hs, you can use the inline header commands to define global 
variables:

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#c
const int HSMYLIBRARY_SOME_VAR = C_MY_VAR;
const char *HSMYLIBRARY_OTHER_VAR = C_OTHER_VAR;
#endc
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And then just bind them with foreign imports like any other variable:

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foreign import ccall "HSMYLIBRARY_SOME_VAR" someVar :: CInt

foreign import ccall "HSMYLIBRARY_OTHER_VAR" otherVarPtr :: Ptr CChar

otherVar :: String
otherVar = unsafePerformIO (peekCString otherVarPtr)
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