Remove compiler warnings

Author: marick

examples/src/PrismsForSumTypes.purs

@@ -7,29 +7,26 @@ module PrismsForSumTypes where
 import Data.Maybe
 
 import Data.Lens
-import Data.Lens as Lens
 import Data.Lens.Prism
 import Color as Color
 import Data.Record.ShowRecord (showRecord)
 import PrismsForSumTypes
-import Data.Number.Approximate
 
 -}
 
 import Prelude
-import Data.Maybe
-import Data.Either
+import Data.Lens (Prism', is, isn't, nearly, only, preview, prism, prism', review)
 
-import Data.Lens
-import Data.Lens as Lens
 import Color (Color)
 import Color as Color
-import Data.Tuple
-import Data.Generic.Rep
+
+import Data.Generic.Rep (class Generic)
 import Data.Generic.Rep.Eq as GEq
 import Data.Generic.Rep.Show as GShow
 import Data.Record.ShowRecord (showRecord)
-import Data.Number.Approximate
+import Data.Maybe (Maybe(..), maybe)
+import Data.Either (Either(..))
+
 
                 {- The types in question -}
 
@@ -95,6 +92,7 @@ solidFocus = prism' constructor focus
 
 -- In real life, you might abbreviate the above to this:
 
+solidFocus' :: Prism' Fill Color
 solidFocus' = prism' Solid case _ of 
   Solid color -> Just color
   _ -> Nothing
@@ -103,17 +101,24 @@ solidFocus' = prism' Solid case _ of
 
 -- After building a prism, you focus in on a color with `preview`:
 
+s1 :: Maybe Color
 s1 = preview solidFocus (Solid Color.white) -- (Just rgba 255 255 255 1.0)
+
+s2 :: Maybe Color
 s2 = preview solidFocus fillRadial -- Nothing
 
 -- ... or you can create a Fill from a color with `review`:
 
+s3 :: Fill
 s3 = review solidFocus Color.white
 -- (Solid rgba 255 255 255 1.0)
 
 -- ... or you can ask whether a given value matches the prism:
 
+s4 :: Boolean
 s4 = is solidFocus fillWhite :: Boolean -- true
+
+s5 :: Boolean
 s5 = isn't solidFocus fillWhite :: Boolean -- false
 
 
@@ -147,22 +152,30 @@ linearFocus = prism constructor focus
 
 -- Even though made differently, this prism is used the same way:
 
+l1 :: String
 l1 = preview linearFocus fillBlackToWhite # maybe "!" showRecord
 -- "{ color1: rgba 0 0 0 1.0, color2: rgba 255 255 255 1.0, percent: (3.3%) }"
 
+l2 :: Fill
 l2 = review linearFocus { color1 : Color.black
                         , color2 : Color.white
                         , percent : Percent 33.3
                         }
 
                 {- Constructing more specific prisms -}
 
--- `only` is used to look for a specific value:
+-- `only` is used to check for a specific value:
 
+whiteSolid :: Prism' Fill Unit
 whiteSolid = only (Solid Color.white)
 
+o1 :: Boolean
 o1 = is whiteSolid (Solid Color.white) :: Boolean -- true
+
+o2 :: Boolean
 o2 = is whiteSolid (Solid Color.black) :: Boolean -- false
+
+o3 :: Boolean
 o3 = is whiteSolid fillRadial :: Boolean -- false
 
 
@@ -189,17 +202,22 @@ brightSolid = nearly (Solid referenceColor) predicate
 -- from `preview`:
 
 
+n1 :: Maybe Unit
 n1 = preview brightSolid (Solid Color.white) -- (Just unit)
 
+n2 :: Maybe Unit
 n2 = preview brightSolid (Solid Color.black) --  Nothing
 
+n3 :: Maybe Unit
 n3 = preview brightSolid NoFill --  Nothing
 
 
 -- So you probably want to use `is` or `isn't`:
 
+n4 :: Boolean
 n4 = is brightSolid (Solid Color.white) :: Boolean -- true
 
 -- You can recover the reference value with `review`:
 
+n5 :: Fill
 n5 = review brightSolid unit -- (Solid rgba 204 204 204 1.0)