-- | Defines 'CutOff' type which is used in "Agda.Interaction.Options".
--   This module's purpose is to eliminate the dependency of
--   "Agda.TypeChecking.Monad.Base" on the termination checker and
--   everything it imports.

module Agda.Termination.CutOff
  ( CutOff(CutOff, DontCutOff)
  , defaultCutOff
  ) where

import Control.DeepSeq

-- | Cut off structural order comparison at some depth in termination checker?

data CutOff
  = CutOff !Int -- ^ @c >= 0@ means: record decrease up to including @c+1@.
  | DontCutOff
  deriving (CutOff -> CutOff -> Bool
(CutOff -> CutOff -> Bool)
-> (CutOff -> CutOff -> Bool) -> Eq CutOff
forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
/= :: CutOff -> CutOff -> Bool
$c/= :: CutOff -> CutOff -> Bool
== :: CutOff -> CutOff -> Bool
$c== :: CutOff -> CutOff -> Bool
Eq , Eq CutOff
Eq CutOff
-> (CutOff -> CutOff -> Ordering)
-> (CutOff -> CutOff -> Bool)
-> (CutOff -> CutOff -> Bool)
-> (CutOff -> CutOff -> Bool)
-> (CutOff -> CutOff -> Bool)
-> (CutOff -> CutOff -> CutOff)
-> (CutOff -> CutOff -> CutOff)
-> Ord CutOff
CutOff -> CutOff -> Bool
CutOff -> CutOff -> Ordering
CutOff -> CutOff -> CutOff
forall a.
Eq a
-> (a -> a -> Ordering)
-> (a -> a -> Bool)
-> (a -> a -> Bool)
-> (a -> a -> Bool)
-> (a -> a -> Bool)
-> (a -> a -> a)
-> (a -> a -> a)
-> Ord a
min :: CutOff -> CutOff -> CutOff
$cmin :: CutOff -> CutOff -> CutOff
max :: CutOff -> CutOff -> CutOff
$cmax :: CutOff -> CutOff -> CutOff
>= :: CutOff -> CutOff -> Bool
$c>= :: CutOff -> CutOff -> Bool
> :: CutOff -> CutOff -> Bool
$c> :: CutOff -> CutOff -> Bool
<= :: CutOff -> CutOff -> Bool
$c<= :: CutOff -> CutOff -> Bool
< :: CutOff -> CutOff -> Bool
$c< :: CutOff -> CutOff -> Bool
compare :: CutOff -> CutOff -> Ordering
$ccompare :: CutOff -> CutOff -> Ordering
$cp1Ord :: Eq CutOff
Ord)

instance Show CutOff where
  show :: CutOff -> String
show (CutOff Int
k) = Int -> String
forall a. Show a => a -> String
show Int
k
  show CutOff
DontCutOff = String
"∞"

instance NFData CutOff where
  rnf :: CutOff -> ()
rnf (CutOff Int
_) = ()
  rnf CutOff
DontCutOff = ()

-- | The default termination depth.

defaultCutOff :: CutOff
defaultCutOff :: CutOff
defaultCutOff = Int -> CutOff
CutOff Int
0 -- minimum value