Merge branch 'parametric-Located' of github.com:diagrams/diagrams-lib…

… into expand

src/Diagrams/Located.hs

@@ -119,16 +119,18 @@ instance Traced a => Traced (Located a) where
 instance Qualifiable a => Qualifiable (Located a) where
   n |> (Loc p a) = Loc p (n |> a)
 
-type instance Codomain (Located a) = Located (Codomain a)
+type instance Codomain (Located a) = Point (Codomain a)
 
-instance (V a ~ V (Codomain a), Parametric a) => Parametric (Located a) where
-  (Loc x a) `atParam` p = Loc x (a `atParam` p)
+instance (Codomain a ~ V a, AdditiveGroup (V a), Parametric a)
+    => Parametric (Located a) where
+  (Loc x a) `atParam` p = x .+^ (a `atParam` p)
 
 instance DomainBounds a => DomainBounds (Located a) where
   domainLower (Loc _ a) = domainLower a
   domainUpper (Loc _ a) = domainUpper a
 
-instance (V a ~ V (Codomain a), EndValues a) => EndValues (Located a)
+instance (Codomain a ~ V a, AdditiveGroup (V a), EndValues a)
+    => EndValues (Located a)
 
 instance ( Codomain a ~ V a, Fractional (Scalar (V a)), AdditiveGroup (V a)
          , Sectionable a, Parametric a
@@ -140,7 +142,9 @@ instance ( Codomain a ~ V a, Fractional (Scalar (V a)), AdditiveGroup (V a)
   reverseDomain (Loc x a) = Loc (x .+^ y) (reverseDomain a)
     where y = a `atParam` (domainUpper a)
 
-instance (HasArcLength a, Fractional (Scalar (V a)), V a ~ V (Codomain a))
+instance ( Codomain a ~ V a, AdditiveGroup (V a), Fractional (Scalar (V a))
+         , HasArcLength a
+         )
     => HasArcLength (Located a) where
   arcLengthBounded eps (Loc _ a)   = arcLengthBounded eps a
   arcLengthToParam eps (Loc _ a) l = arcLengthToParam eps a l

src/Diagrams/TwoD.hs

@@ -70,14 +70,14 @@ module Diagrams.TwoD
          -- * Angles
        , tau
        , Angle(..)
-       , Turn(..), CircleFrac, Rad(..), Deg(..)
+       , Turn(..), asTurn, CircleFrac, Rad(..), asRad, Deg(..), asDeg
        , fullCircle, convertAngle
 
          -- * Paths
          -- ** Stroking
        , stroke, stroke', strokeTrail, strokeT, strokeTrail', strokeT'
        , strokeLine, strokeLoop
-       , strokeLocT, strokeLocLine, strokeLocLoop
+       , strokeLocTrail, strokeLocT, strokeLocLine, strokeLocLoop
        , FillRule(..), fillRule
        , StrokeOpts(..)
 

src/Diagrams/TwoD/Path.hs

@@ -25,7 +25,7 @@ module Diagrams.TwoD.Path
 
          stroke, stroke', strokeTrail, strokeT, strokeTrail', strokeT'
        , strokeLine, strokeLoop
-       , strokeLocT, strokeLocLine, strokeLocLoop
+       , strokeLocTrail, strokeLocT, strokeLocLine, strokeLocLoop
 
          -- ** Stroke options
 
@@ -201,9 +201,13 @@ strokeLoop :: (Renderable (Path R2) b) => Trail' Loop R2 -> Diagram b R2
 strokeLoop = strokeT . wrapLoop
 
 -- | A convenience function for converting a @Located Trail@ directly
---   into a diagram; @strokeLocT = stroke . trailLike@.
+--   into a diagram; @strokeLocTrail = stroke . trailLike@.
+strokeLocTrail :: (Renderable (Path R2) b) => Located (Trail R2) -> Diagram b R2
+strokeLocTrail = stroke . trailLike
+
+-- | Deprecated synonym for 'strokeLocTrail'.
 strokeLocT :: (Renderable (Path R2) b) => Located (Trail R2) -> Diagram b R2
-strokeLocT = stroke . trailLike
+strokeLocT = strokeLocTrail
 
 -- | A convenience function for converting a @Located@ line directly
 --   into a diagram; @strokeLocLine = stroke . trailLike . mapLoc wrapLine@.

src/Diagrams/TwoD/Types.hs

@@ -26,7 +26,7 @@ module Diagrams.TwoD.Types
 
          -- * Angles
        , Angle(..)
-       , Turn(..), CircleFrac, Rad(..), Deg(..)
+       , Turn(..), asTurn, CircleFrac, Rad(..), asRad, Deg(..), asDeg
        , fullCircle, convertAngle
        ) where
 
@@ -198,17 +198,41 @@ instance Transformable R2 where
 newtype Turn = Turn { getTurn :: Double }
   deriving (Read, Show, Eq, Ord, Enum, Fractional, Num, Real, RealFrac)
 
+-- | The identity function with a restricted type, for conveniently
+-- declaring that some value should have type 'Turn'.  For example,
+-- @rotation . asTurn . fromRational@ constructs a rotation from a
+-- rational value considered as a @Turn@.  Without @asTurn@, the angle
+-- type would be ambiguous.
+asTurn :: Turn -> Turn
+asTurn = id
+
 -- | Deprecated synonym for 'Turn', retained for backwards compatibility.
 type CircleFrac = Turn
 
 -- | Newtype wrapper for representing angles in radians.
 newtype Rad = Rad { getRad :: Double }
   deriving (Read, Show, Eq, Ord, Enum, Floating, Fractional, Num, Real, RealFloat, RealFrac)
 
+-- | The identity function with a restricted type, for conveniently
+-- declaring that some value should have type 'Rad'.  For example,
+-- @rotation . asRad . fromRational@ constructs a rotation from a
+-- rational value considered as a value in radians.  Without @asRad@,
+-- the angle type would be ambiguous.
+asRad :: Rad -> Rad
+asRad = id
+
 -- | Newtype wrapper for representing angles in degrees.
 newtype Deg = Deg { getDeg :: Double }
   deriving (Read, Show, Eq, Ord, Enum, Fractional, Num, Real, RealFrac)
 
+-- | The identity function with a restricted type, for conveniently
+-- declaring that some value should have type 'Deg'.  For example,
+-- @rotation . asDeg . fromIntegral@ constructs a rotation from an
+-- integral value considered as a value in degrees.  Without @asDeg@,
+-- the angle type would be ambiguous.
+asDeg :: Deg -> Deg
+asDeg = id
+
 -- | Type class for types that measure angles.
 class Num a => Angle a where
   -- | Convert to a turn, /i.e./ a fraction of a circle.