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1. tupleNameDegree_maybe :: Name -> Maybe Int

   th-desugar	Language.Haskell.TH.Desugar

   Extract the degree of a tuple Name. In addition to recognizing tuple syntax (e.g., ''(,,)), this also recognizes the following:

   • ''Unit (for 0-tuples)
   • ''Solo/'MkSolo (for 1-tuples)
   • ''TupleN (for N-tuples)
   In recent versions of GHC, ''() is a synonym for ''Unit, ''(,) is a synonym for ''Tuple2, and so on. As a result, we must check for ''Unit and ''TupleN in tupleDegree_maybe to be thorough. (There is no special tuple syntax for ''Solo/'MkSolo, but we check them here as well for the sake of completeness.)

2. unboxedSumNameDegree_maybe :: Name -> Maybe Int

   th-desugar	Language.Haskell.TH.Desugar

   Extract the degree of an unboxed sum Name. In addition to recognizing unboxed sum syntax (e.g., ''()), this also recognizes ''SumN# (for unboxed N-ary sum type constructors). In recent versions of GHC, ''Sum2# is a synonym for ''(), ''Sum3# is a synonym for ''(), and so on. As a result, we must check for ''SumN# in unboxedSumNameDegree_maybe to be thorough.

3. unboxedTupleNameDegree_maybe :: Name -> Maybe Int

   th-desugar	Language.Haskell.TH.Desugar

   Extract the degree of an unboxed tuple Name. In addition to recognizing unboxed tuple syntax (e.g., ''()), this also recognizes the following:

   • ''Unit# (for unboxed 0-tuples)
   • ''Solo#/'Solo# (for unboxed 1-tuples)
   • ''TupleN# (for unboxed N-tuples)
   In recent versions of GHC, ''(##) is a synonym for ''Unit#, ''() is a synonym for ''Tuple2#, and so on. As a result, we must check for ''Unit#, and ''TupleN in unboxedTupleNameDegree_maybe to be thorough. (There is no special unboxed tuple type constructor for ''Solo#/'Solo#, but we check them here as well for the sake of completeness.)

4. unionMaybeSubsts :: [Maybe DSubst] -> Maybe DSubst

   th-desugar	Language.Haskell.TH.Desugar.Subst

   No documentation available.

5. catMaybes :: [Maybe a] -> [a]

   HaXml	Text.XML.HaXml.XmlContent.Parser

   The catMaybes function takes a list of Maybes and returns a list of all the Just values.

   Examples

   Basic usage:

   >>> catMaybes [Just 1, Nothing, Just 3]
   [1,3]
   

   When constructing a list of Maybe values, catMaybes can be used to return all of the "success" results (if the list is the result of a map, then mapMaybe would be more appropriate):

   >>> import GHC.Internal.Text.Read ( readMaybe )
   
   >>> [readMaybe x :: Maybe Int | x <- ["1", "Foo", "3"] ]
   [Just 1,Nothing,Just 3]
   
   >>> catMaybes $ [readMaybe x :: Maybe Int | x <- ["1", "Foo", "3"] ]
   [1,3]
   

6. forceMaybe :: Maybe a -> a

   MissingH	Data.Maybe.Utils

   Pulls a Just value out of a Maybe value. If the Maybe value is Nothing, raises an exception with error. Alias of fromJust.

7. forceMaybeMsg :: String -> Maybe a -> a

   MissingH	Data.Maybe.Utils

   Like forceMaybe, but lets you customize the error message raised if Nothing is supplied.

8. cast'Maybe :: Val a => Value -> Maybe (Maybe a)

   bson	Data.Bson

   No documentation available.

9. valMaybe :: Val a => Maybe a -> Value

   bson	Data.Bson

   No documentation available.

10. updateViewStateWithEventMaybe :: Event -> ViewState -> Maybe ViewState

    gloss	Graphics.Gloss.Data.ViewState

    Like updateViewStateWithEvent, but returns Nothing if no update was needed.

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