tcfail067.hs:1:14: warning:
-XDatatypeContexts is deprecated: It was widely considered a misfeature, and has been removed from the Haskell language.
tcfail067.hs:12:16: error:
• No instance for (Ord a) arising from a use of ‘SubRange’
Possible fix:
add (Ord a) to the context of
the type signature for:
subRangeValue :: SubRange a -> a
• In the pattern: SubRange (lower, upper) value
In an equation for ‘subRangeValue’:
subRangeValue (SubRange (lower, upper) value) = value
tcfail067.hs:15:11: error:
• No instance for (Ord a) arising from a use of ‘SubRange’
Possible fix:
add (Ord a) to the context of
the type signature for:
subRange :: SubRange a -> (a, a)
• In the pattern: SubRange r value
In an equation for ‘subRange’: subRange (SubRange r value) = r
tcfail067.hs:46:12: error:
• Could not deduce (Ord a) arising from a use of ‘SubRange’
from the context: Show a
bound by the type signature for:
showRange :: Show a => SubRange a -> String
at tcfail067.hs:45:1-43
Possible fix:
add (Ord a) to the context of
the type signature for:
showRange :: Show a => SubRange a -> String
• In the pattern: SubRange (lower, upper) value
In an equation for ‘showRange’:
showRange (SubRange (lower, upper) value)
= show value ++ " :" ++ show lower ++ ".." ++ show upper
tcfail067.hs:61:12: error:
• Could not deduce (Ord a)
arising from a use of ‘numSubRangeNegate’
from the context: Num a
bound by the instance declaration at tcfail067.hs:60:10-34
Possible fix:
add (Ord a) to the context of the instance declaration
• In the expression: numSubRangeNegate
In an equation for ‘negate’: negate = numSubRangeNegate
In the instance declaration for ‘Num (SubRange a)’
tcfail067.hs:65:19: error:
• Could not deduce (Ord a) arising from a use of ‘SubRange’
from the context: Num a
bound by the instance declaration at tcfail067.hs:60:10-34
Possible fix:
add (Ord a) to the context of the instance declaration
• In the expression:
SubRange (fromInteger a, fromInteger a) (fromInteger a)
In an equation for ‘fromInteger’:
fromInteger a
= SubRange (fromInteger a, fromInteger a) (fromInteger a)
In the instance declaration for ‘Num (SubRange a)’
tcfail067.hs:74:5: error:
• Could not deduce (Ord a) arising from a use of ‘SubRange’
from the context: Num a
bound by the type signature for:
numSubRangeBinOp :: Num a =>
(a -> a -> a) -> SubRange a -> SubRange a -> SubRange a
at tcfail067.hs:(71,1)-(72,58)
Possible fix:
add (Ord a) to the context of
the type signature for:
numSubRangeBinOp :: Num a =>
(a -> a -> a) -> SubRange a -> SubRange a -> SubRange a
• In the expression: SubRange (result, result) result
In an equation for ‘numSubRangeBinOp’:
numSubRangeBinOp op a b
= SubRange (result, result) result
where
result = (subRangeValue a) `op` (subRangeValue b)