[Haskell-cafe] getting the name of a function for test diagnostic purposes

[Daniel Fischer]

Am Donnerstag, 3. März 2005 14:28 schrieb Terrence Brannon:
> {-
> I have written a program (below) to run a test suite for a list of
> functions:
>
>     [isTotalJunc, isPartialJunc]
>
> where each function receives a datum of type ApplyArg whose value slot is
> one element at a time of the list of types below:
>
>     [JNone, JOne, JAny, JAll]
>
> I therefore must run 8 tests (the cross product of functions and types).
>
> Right now, here is the output:
>
> *Main> test_total_partial
> ["fun: (->)input: JNoneoutput: True","fun: (->)input: JOneoutput:
> False","fun: (->)input: JAnyoutput: False","fun: (->)input: JAlloutput:
> True","fun: (->)input: JNoneoutput: False","fun: (->)input: JOneoutput:
> True","fun: (->)input: JAnyoutput: True","fun: (->)input: JAlloutput:
> False"]
>
>   -- One problem is that functions do not print as their name. The
>      call to (show f) in showres simply yields (->)
>
>   -- Another problem is that I cannot manage to separate each string
>      with a carriage return.
>
> Any help with these problems is appreciated.
>
> -}
>
> test_total_partial = let funs  = [isTotalJunc, isPartialJunc]
> 			 types = [JNone, JOne, JAny, JAll]
> 			 mkdat typ = ApplyArg "somename" (VJunc $ Junc typ emptySet emptySet)
> False showres f t r = "fun: " ++ (show f) ++ "input: " ++ (show t) ++
                                                                      ^
> "output: " ++ (show r) runtest f t = do {
    ^
   insert a space here?

> 					   retval <- f (mkdat t);
> 					   return $ (showres f t retval)
> 					  }
> 			 in
>   [ (showres f t (f (mkdat t))) | f <- funs, t <- types ]

In the case where you want to test a few known functions, you might do 
something like

[(fun1,"fun1"),(fun2,"fun2")]

and 

... in
putStr . unlines $ [showRes fname t (f (mkdat t)) | (f,fname) <- funns, t <- 
types]

Of course, it's very specific, but it will produce better formatted output.

Daniel