| definition: |
genShowP :: String -> FC.TypeDecl -> CInstanceDecl
genShowP _ (FC.TypeSyn _ _ _ _) =
error "genShowP: cannot translate type synonyms"
genShowP _ (FC.TypeNew _ _ _ _) =
error "genShowP: cannot translate newtypes"
genShowP mainmod (FC.Type qtc@(_,tc) _ tvars consdecls) =
CInstance (pre "Show")
(CContext (map (\tv -> (pre "Show", [CTVar tv])) polyavars))
[applyTC (mainmod,t2bt tc) (map CTVar polyavars)]
[cfunc
(pre "show") 1 Public
(emptyClassType
(applyTC (mainmod,t2bt tc) (map CTVar polyavars) ~> stringType))
(simpleRule [CPComb (mainmod, "Bot_" ++ transQN tc) []]
(constF (mainmod, "bottomValue")) :
if isPrimExtType qtc
then [valueRule]
else map genConsRule consdecls)]
where
-- variables for polymorphic type arguments:
polyavars = [ (i,"a" ++ show i) | i <- map fst tvars]
genConsRule (FC.Cons (_,cons) _ _ argtypes) =
let args = [(i,"x" ++ show i) | i <- [0 .. length argtypes - 1]]
showargs = map (\v -> applyF (pre "show") [CVar v]) args
in simpleRule [CPComb (mainmod,t2bt cons) (map CPVar args)]
(if null showargs
then string2ac cons
else applyF (mainmod,"constrValue")
[list2ac (string2ac cons : showargs)])
valueRule =
let var = (0,"x")
in simpleRule [CPComb (mainmod,"Value_"++tc) [CPVar var]]
(applyF (pre "show") [CVar var])
|
| demand: |
argument 2 |
| deterministic: |
deterministic operation |
| documentation: |
-------------------------------------------------------------------------
-- Create a instance declaration for `Show` for a data type with
-- explicit bottom constructors according to the following scheme:
{-
instance Show P_AB where
show Bot_AB = "failed"
show P_A = "A"
show P_B = "B"
instance Show P_C where
show Bot_C = "failed"
show (P_C x) = "(C" ++ show x ")"
-}
|
| indeterministic: |
referentially transparent operation |
| infix: |
no fixity defined |
| name: |
genShowP |
| precedence: |
no precedence defined |
| result-values: |
{CInstance}
|
| signature: |
String -> FlatCurry.Types.TypeDecl -> AbstractCurry.Types.CInstanceDecl |
| solution-complete: |
operation might suspend on free variables |
| terminating: |
possibly non-terminating |
| totally-defined: |
possibly non-reducible on same data term |