never executed always true always false

    1 {-# LANGUAGE QuasiQuotes #-}
    2 
    3 module Conjure.Process.DealWithCuts ( dealWithCuts ) where
    4 
    5 import Conjure.Prelude
    6 import Conjure.UserError
    7 import Conjure.Language.Definition
    8 import Conjure.Language.Domain
    9 import Conjure.Language.TH
   10 import Conjure.Language.ModelStats ( finds )
   11 
   12 
   13 dealWithCuts
   14     :: (MonadFailDoc m, NameGen m, MonadUserError m)
   15     => Model
   16     -> m Model
   17 dealWithCuts m = do
   18     statements <- forM (mStatements m) $ \ statement ->
   19         case statement of
   20             SearchOrder orders0 -> do
   21                 (orders1, (newVars, newCons)) <- runWriterT $ forM orders0 $ \ order ->
   22                     case order of
   23                         Cut x -> do
   24                             varName <- nextName "cut"
   25                             let varDecl = Declaration (FindOrGiven Find varName DomainBool)
   26                             let varRef  = Reference varName (Just (DeclNoRepr Find varName DomainBool NoRegion))
   27                             tell ( [ varDecl ]
   28                                  , [ [essence| !&varRef <-> &x |] ]
   29                                  )
   30                             return $ BranchingOn varName
   31                         _ -> return order
   32                 orders2 <-
   33                         if null [ () | BranchingOn{} <- orders0 ]     -- no variables were given, all assumed non-aux
   34                             then return [ BranchingOn nm | (nm, _) <- finds m ]
   35                             else return []
   36                 return $ concat
   37                     [ newVars
   38                     , [SearchOrder (orders1++orders2)]
   39                     , [SuchThat newCons]
   40                     ]
   41             _ -> return [statement]
   42     return m { mStatements = concat statements }