Default instance for constructor frequencies

generic-boltzmann-brain.cabal

@@ -43,6 +43,7 @@ library
       QuickCheck >=2.14.2
     , base >=4.7 && <5
     , containers >=0.6.4
+    , data-default >=0.7.1.1
     , mtl >=2.2.2
     , paganini-hs >=0.3.0.0
     , random >=1.2.0
@@ -69,6 +70,7 @@ executable binTreeProfile
       QuickCheck >=2.14.2
     , base >=4.7 && <5
     , containers >=0.6.4
+    , data-default >=0.7.1.1
     , generic-boltzmann-brain
     , mtl >=2.2.2
     , paganini-hs >=0.3.0.0
@@ -96,6 +98,7 @@ executable lambdaProfile
       QuickCheck >=2.14.2
     , base >=4.7 && <5
     , containers >=0.6.4
+    , data-default >=0.7.1.1
     , generic-boltzmann-brain
     , mtl >=2.2.2
     , paganini-hs >=0.3.0.0
@@ -123,6 +126,7 @@ executable treeProfile
       QuickCheck >=2.14.2
     , base >=4.7 && <5
     , containers >=0.6.4
+    , data-default >=0.7.1.1
     , generic-boltzmann-brain
     , mtl >=2.2.2
     , paganini-hs >=0.3.0.0
@@ -151,6 +155,7 @@ test-suite generic-boltzmann-brain-test
       QuickCheck >=2.14.2
     , base >=4.7 && <5
     , containers >=0.6.4
+    , data-default >=0.7.1.1
     , generic-boltzmann-brain
     , mtl >=2.2.2
     , paganini-hs >=0.3.0.0

package.yaml

@@ -32,6 +32,7 @@ dependencies:
 - paganini-hs >= 0.3.0.0
 - QuickCheck >= 2.14.2
 - splitmix >= 0.1.0.4
+- data-default >= 0.7.1.1
 
 library:
   source-dirs: src

profile/BinTree/BinTree.hs

@@ -6,11 +6,11 @@ import Control.Monad (replicateM)
 import Data.Boltzmann.BitOracle (evalIO)
 import Data.Boltzmann.Sampler (BoltzmannSampler (..), rejectionSampler')
 import Data.Boltzmann.System (
-  ConstructorFrequencies (MkConstructorFrequencies),
   ConstructorWeights (MkConstructorWeights),
   System (..),
  )
 import Data.Boltzmann.System.TH (mkBoltzmannSampler)
+import Data.Default (Default (def))
 import System.Random.SplitMix (SMGen)
 
 data BinTree
@@ -22,7 +22,7 @@ mkBoltzmannSampler
   System
     { targetType = ''BinTree
     , meanSize = 1000
-    , frequencies = MkConstructorFrequencies []
+    , frequencies = def
     , weights =
         MkConstructorWeights
           [ ('Leaf, 0)

profile/Lambda/Lambda.hs

@@ -11,6 +11,7 @@ import Data.Boltzmann.System (
   System (..),
  )
 import Data.Boltzmann.System.TH (mkBoltzmannSampler)
+import Data.Default (Default (def))
 import System.Random.SplitMix (SMGen)
 
 data DeBruijn
@@ -28,7 +29,7 @@ mkBoltzmannSampler
   System
     { targetType = ''Lambda
     , meanSize = 10_000
-    , frequencies = MkConstructorFrequencies []
+    , frequencies = def
     , weights =
         MkConstructorWeights
           [ -- De Bruijn

profile/Tree/Tree.hs

@@ -6,11 +6,11 @@ import Control.Monad (replicateM)
 import Data.Boltzmann.BitOracle (evalIO)
 import Data.Boltzmann.Sampler (BoltzmannSampler (..), rejectionSampler')
 import Data.Boltzmann.System (
-  ConstructorFrequencies (MkConstructorFrequencies),
   ConstructorWeights (MkConstructorWeights),
   System (..),
  )
 import Data.Boltzmann.System.TH (mkBoltzmannSampler)
+import Data.Default (Default (def))
 import System.Random.SplitMix (SMGen)
 
 data Tree = T [Tree]
@@ -20,7 +20,7 @@ mkBoltzmannSampler
   System
     { targetType = ''Tree
     , meanSize = 1000
-    , frequencies = MkConstructorFrequencies []
+    , frequencies = def
     , weights =
         MkConstructorWeights
           [ ('T, 1)
@@ -38,7 +38,7 @@ mkBoltzmannSampler
   System
     { targetType = ''Tree'
     , meanSize = 2000
-    , frequencies = MkConstructorFrequencies []
+    , frequencies = def
     , weights =
         MkConstructorWeights
           [ ('T, 1)

src/Data/Boltzmann/System.hs

@@ -44,6 +44,7 @@ import Language.Haskell.TH.Datatype (
  )
 
 import Data.Coerce (coerce)
+import Data.Default (Default (def))
 import Prelude hiding (seq)
 
 newtype ConstructorWeights = MkConstructorWeights
@@ -54,6 +55,9 @@ newtype ConstructorFrequencies = MkConstructorFrequencies
   {unConstructorFrequencies :: [(Name, Int)]}
   deriving (Show) via [(Name, Int)]
 
+instance Default ConstructorFrequencies where
+  def = MkConstructorFrequencies []
+
 data System = System
   { targetType :: Name
   , meanSize :: Int