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1. isValid :: FilePath -> Bool

   rio	RIO.FilePath

   Is a FilePath valid, i.e. could you create a file like it? This function checks for invalid names, and invalid characters, but does not check if length limits are exceeded, as these are typically filesystem dependent.

   isValid "" == False
   isValid "\0" == False
   Posix:   isValid "/random_ path:*" == True
   Posix:   isValid x == not (null x)
   Windows: isValid "c:\\test" == True
   Windows: isValid "c:\\test:of_test" == False
   Windows: isValid "test*" == False
   Windows: isValid "c:\\test\\nul" == False
   Windows: isValid "c:\\test\\prn.txt" == False
   Windows: isValid "c:\\nul\\file" == False
   Windows: isValid "\\\\" == False
   Windows: isValid "\\\\\\foo" == False
   Windows: isValid "\\\\?\\D:file" == False
   Windows: isValid "foo\tbar" == False
   Windows: isValid "nul .txt" == False
   Windows: isValid " nul.txt" == True
   

2. makeValid :: FilePath -> FilePath

   rio	RIO.FilePath

   Take a FilePath and make it valid; does not change already valid FILEPATHs.

   isValid (makeValid x)
   isValid x ==> makeValid x == x
   makeValid "" == "_"
   makeValid "file\0name" == "file_name"
   Windows: makeValid "c:\\already\\/valid" == "c:\\already\\/valid"
   Windows: makeValid "c:\\test:of_test" == "c:\\test_of_test"
   Windows: makeValid "test*" == "test_"
   Windows: makeValid "c:\\test\\nul" == "c:\\test\\nul_"
   Windows: makeValid "c:\\test\\prn.txt" == "c:\\test\\prn_.txt"
   Windows: makeValid "c:\\test/prn.txt" == "c:\\test/prn_.txt"
   Windows: makeValid "c:\\nul\\file" == "c:\\nul_\\file"
   Windows: makeValid "\\\\\\foo" == "\\\\drive"
   Windows: makeValid "\\\\?\\D:file" == "\\\\?\\D:\\file"
   Windows: makeValid "nul .txt" == "nul _.txt"
   

3. valid :: Ord k => Map k a -> Bool

   rio	RIO.Map

   Test if the internal map structure is valid.

   valid (fromAscList [(3,"b"), (5,"a")]) == True
   valid (fromAscList [(5,"a"), (3,"b")]) == False
   

4. void :: Functor f => f a -> f ()

   rio	RIO.Prelude

   void value discards or ignores the result of evaluation, such as the return value of an IO action.

   Examples

   Replace the contents of a Maybe Int with unit:

   >>> void Nothing
   Nothing
   

   >>> void (Just 3)
   Just ()
   

   Replace the contents of an Either Int Int with unit, resulting in an Either Int ():

   >>> void (Left 8675309)
   Left 8675309
   

   >>> void (Right 8675309)
   Right ()
   

   Replace every element of a list with unit:

   >>> void [1,2,3]
   [(),(),()]
   

   Replace the second element of a pair with unit:

   >>> void (1,2)
   (1,())
   

   Discard the result of an IO action:

   >>> mapM print [1,2]
   1
   2
   [(),()]
   

   >>> void $ mapM print [1,2]
   1
   2
   

5. class Semigroup a => Monoid a

   rio	RIO.Prelude.Types

   The class of monoids (types with an associative binary operation that has an identity). Instances should satisfy the following:

   • Right identity x <> mempty = x
   • Left identity mempty <> x = x
   • Associativity x <> (y <> z) = (x <> y) <> z (Semigroup law)
   • Concatenation mconcat = foldr (<>) mempty
   You can alternatively define mconcat instead of mempty, in which case the laws are:
   • Unit mconcat (pure x) = x
   • Multiplication mconcat (join xss) = mconcat (fmap mconcat xss)
   • Subclass mconcat (toList xs) = sconcat xs
   The method names refer to the monoid of lists under concatenation, but there are many other instances. Some types can be viewed as a monoid in more than one way, e.g. both addition and multiplication on numbers. In such cases we often define newtypes and make those instances of Monoid, e.g. Sum and Product. NOTE: Semigroup is a superclass of Monoid since base-4.11.0.0.

6. data Void

   rio	RIO.Prelude.Types

   Uninhabited data type

7. runIdentity :: Identity a -> a

   rio	RIO.Prelude.Types

   No documentation available.

8. PathsInvalidInPath :: [FilePath] -> ProcessException

   rio	RIO.Process

   No documentation available.

9. valid :: Ord a => Set a -> Bool

   rio	RIO.Set

   Test if the internal set structure is valid.

10. Friday :: DayOfWeek

    rio	RIO.Time

    No documentation available.

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