Difference between revisions of "GHC/Error messages"
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This error message occurs when one tries to instantiate a class, but did not import the functions one tries to implement. |
This error message occurs when one tries to instantiate a class, but did not import the functions one tries to implement. |
||
− | Example: |
+ | Example: |
+ | <haskell> |
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+ | import Prelude hiding ((==)) |
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+ | data Foo = Foo |
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+ | instance Eq Foo where |
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+ | (==) a b = True |
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+ | </haskell> |
Revision as of 17:07, 9 October 2009
GHC error messages and their meaning.
"Parse error in pattern"
TODO
Example: TODO
"Foo' is not a (visible) method of class `Bar'"
This error message occurs when one tries to instantiate a class, but did not import the functions one tries to implement.
Example:
import Prelude hiding ((==))
data Foo = Foo
instance Eq Foo where
(==) a b = True