Derive Generic instances

Author: wereHamster

src/Data/Date.purs

@@ -25,6 +25,7 @@ import Data.Enum (Enum, Cardinality(..), fromEnum, defaultSucc, defaultPred)
 import Data.Function (on, Fn2(), runFn2, Fn3(), runFn3)
 import Data.Maybe (Maybe(..))
 import Data.Time
+import Data.Generic
 
 -- | A native JavaScript `Date` object.
 foreign import data JSDate :: *
@@ -36,6 +37,14 @@ foreign import data JSDate :: *
 -- | modules.
 newtype Date = DateTime JSDate
 
+instance genericDate :: Generic Date where
+  toSpine d = SProd "Date" [const (toSpine $ toEpochMilliseconds d)]
+  toSignature _ = SigProd [{ sigConstructor: "Date", sigValues: [const SigNumber] }]
+  fromSpine (SProd "Date" [msf]) = case msf unit of
+    (SNumber ms) -> fromEpochMilliseconds $ Milliseconds ms
+    _            -> Nothing
+  fromSpine _ = Nothing
+
 instance eqDate :: Eq Date where
   eq = eq `on` toEpochMilliseconds
 

src/Data/Time.purs

@@ -19,10 +19,14 @@ import Prelude
   , compare
   , show )
 
+import Data.Generic
+
 -- | An hour component from a time value. Should fall between 0 and 23
 -- | inclusive.
 newtype HourOfDay = HourOfDay Int
 
+derive instance genericHourOfDay :: Generic HourOfDay
+
 instance eqHourOfDay :: Eq HourOfDay where
   eq (HourOfDay x) (HourOfDay y) = x == y
 
@@ -32,6 +36,8 @@ instance ordHourOfDay :: Ord HourOfDay where
 -- | A quantity of hours (not necessarily a value between 0 and 23).
 newtype Hours = Hours Number
 
+derive instance genericHours :: Generic Hours
+
 instance eqHours :: Eq Hours where
   eq (Hours x) (Hours y) = x == y
 
@@ -62,6 +68,8 @@ instance showHours :: Show Hours where
 -- | inclusive.
 newtype MinuteOfHour = MinuteOfHour Int
 
+derive instance genericMinuteOfHour :: Generic MinuteOfHour
+
 instance eqMinuteOfHour :: Eq MinuteOfHour where
   eq (MinuteOfHour x) (MinuteOfHour y) = x == y
 
@@ -71,6 +79,8 @@ instance ordMinuteOfHour :: Ord MinuteOfHour where
 -- | A quantity of minutes (not necessarily a value between 0 and 60).
 newtype Minutes = Minutes Number
 
+derive instance genericMinutes :: Generic Minutes
+
 instance eqMinutes :: Eq Minutes where
   eq (Minutes x) (Minutes y) = x == y
 
@@ -101,6 +111,8 @@ instance showMinutes :: Show Minutes where
 -- | inclusive.
 newtype SecondOfMinute = SecondOfMinute Int
 
+derive instance genericSecondOfMinute :: Generic SecondOfMinute
+
 instance eqSecondOfMinute :: Eq SecondOfMinute where
   eq (SecondOfMinute x) (SecondOfMinute y) = x == y
 
@@ -110,6 +122,8 @@ instance ordSecondOfMinute :: Ord SecondOfMinute where
 -- | A quantity of seconds (not necessarily a value between 0 and 60).
 newtype Seconds = Seconds Number
 
+derive instance genericSeconds :: Generic Seconds
+
 instance eqSeconds :: Eq Seconds where
   eq (Seconds x) (Seconds y) = x == y
 
@@ -140,6 +154,8 @@ instance showSeconds :: Show Seconds where
 -- | inclusive.
 newtype MillisecondOfSecond = MillisecondOfSecond Int
 
+derive instance genericMillisecondOfSecond :: Generic MillisecondOfSecond
+
 instance eqMillisecondOfSecond :: Eq MillisecondOfSecond where
   eq (MillisecondOfSecond x) (MillisecondOfSecond y) = x == y
 
@@ -149,6 +165,8 @@ instance ordMillisecondOfSecond :: Ord MillisecondOfSecond where
 -- | A quantity of milliseconds (not necessarily a value between 0 and 1000).
 newtype Milliseconds = Milliseconds Number
 
+derive instance genericMilliseconds :: Generic Milliseconds
+
 instance eqMilliseconds :: Eq Milliseconds where
   eq (Milliseconds x) (Milliseconds y) = x == y