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1. isJust :: Maybe a -> Bool

   base	Data.Maybe

   The isJust function returns True iff its argument is of the form Just _.

   Examples

   Basic usage:

   >>> isJust (Just 3)
   True
   

   >>> isJust (Just ())
   True
   

   >>> isJust Nothing
   False
   

   Only the outer constructor is taken into consideration:

   >>> isJust (Just Nothing)
   True
   

2. catchJust :: Exception e => (e -> Maybe b) -> IO a -> (b -> IO a) -> IO a

   base	Control.Exception

   The function catchJust is like catch, but it takes an extra argument which is an exception predicate, a function which selects which type of exceptions we're interested in.

   catchJust (\e -> if isDoesNotExistErrorType (ioeGetErrorType e) then Just () else Nothing)
   (readFile f)
   (\_ -> do hPutStrLn stderr ("No such file: " ++ show f)
   return "")
   

   Any other exceptions which are not matched by the predicate are re-raised, and may be caught by an enclosing catch, catchJust, etc.

3. handleJust :: Exception e => (e -> Maybe b) -> (b -> IO a) -> IO a -> IO a

   base	Control.Exception

   A version of catchJust with the arguments swapped around (see handle).

4. tryJust :: Exception e => (e -> Maybe b) -> IO a -> IO (Either b a)

   base	Control.Exception

   A variant of try that takes an exception predicate to select which exceptions are caught (c.f. catchJust). If the exception does not match the predicate, it is re-thrown.

5. catchJust :: Exception e => (e -> Maybe b) -> IO a -> (b -> IO a) -> IO a

   base	Control.Exception.Base

   The function catchJust is like catch, but it takes an extra argument which is an exception predicate, a function which selects which type of exceptions we're interested in.

   catchJust (\e -> if isDoesNotExistErrorType (ioeGetErrorType e) then Just () else Nothing)
   (readFile f)
   (\_ -> do hPutStrLn stderr ("No such file: " ++ show f)
   return "")
   

   Any other exceptions which are not matched by the predicate are re-raised, and may be caught by an enclosing catch, catchJust, etc.

6. handleJust :: Exception e => (e -> Maybe b) -> (b -> IO a) -> IO a -> IO a

   base	Control.Exception.Base

   A version of catchJust with the arguments swapped around (see handle).

7. tryJust :: Exception e => (e -> Maybe b) -> IO a -> IO (Either b a)

   base	Control.Exception.Base

   A variant of try that takes an exception predicate to select which exceptions are caught (c.f. catchJust). If the exception does not match the predicate, it is re-thrown.

8. data FormatAdjustment

   base	Text.Printf

   Whether to left-adjust or zero-pad a field. These are mutually exclusive, with LeftAdjust taking precedence.

9. LeftAdjust :: FormatAdjustment

   base	Text.Printf

   No documentation available.

10. fmtAdjust :: FieldFormat -> Maybe FormatAdjustment

    base	Text.Printf

    Kind of filling or padding to be done.

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