YES 0.842 H-Termination proof of /home/matraf/haskell/eval_FullyBlown_Fast/empty.hs
H-Termination of the given Haskell-Program with start terms could successfully be proven:



HASKELL
  ↳ LR

mainModule Main
  ((splitAt :: Int  ->  [a ->  ([a],[a])) :: Int  ->  [a ->  ([a],[a]))

module Main where
  import qualified Prelude



Lambda Reductions:
The following Lambda expression
\(xs',_)→xs'

is transformed to
xs'0 (xs',_) = xs'

The following Lambda expression
\(_,xs'')→xs''

is transformed to
xs''0 (_,xs'') = xs''



↳ HASKELL
  ↳ LR
HASKELL
      ↳ BR

mainModule Main
  ((splitAt :: Int  ->  [a ->  ([a],[a])) :: Int  ->  [a ->  ([a],[a]))

module Main where
  import qualified Prelude



Replaced joker patterns by fresh variables and removed binding patterns.

↳ HASKELL
  ↳ LR
    ↳ HASKELL
      ↳ BR
HASKELL
          ↳ COR

mainModule Main
  ((splitAt :: Int  ->  [a ->  ([a],[a])) :: Int  ->  [a ->  ([a],[a]))

module Main where
  import qualified Prelude



Cond Reductions:
The following Function with conditions
undefined 
 | False
 = undefined

is transformed to
undefined  = undefined1

undefined0 True = undefined

undefined1  = undefined0 False

The following Function with conditions
splitAt n xs
 | n <= 0
 = ([],xs)
splitAt vw [] = ([],[])
splitAt n (x : xs) = 
(x : xs',xs'')
where 
vu42  = splitAt (n - 1) xs
xs'  = xs'0 vu42
xs''  = xs''0 vu42
xs''0 (vx,xs'') = xs''
xs'0 (xs',vy) = xs'

is transformed to
splitAt n xs = splitAt3 n xs
splitAt vw [] = splitAt1 vw []
splitAt n (x : xs) = splitAt0 n (x : xs)

splitAt0 n (x : xs) = 
(x : xs',xs'')
where 
vu42  = splitAt (n - 1) xs
xs'  = xs'0 vu42
xs''  = xs''0 vu42
xs''0 (vx,xs'') = xs''
xs'0 (xs',vy) = xs'

splitAt1 vw [] = ([],[])
splitAt1 ww wx = splitAt0 ww wx

splitAt2 n xs True = ([],xs)
splitAt2 n xs False = splitAt1 n xs

splitAt3 n xs = splitAt2 n xs (n <= 0)
splitAt3 wy wz = splitAt1 wy wz



↳ HASKELL
  ↳ LR
    ↳ HASKELL
      ↳ BR
        ↳ HASKELL
          ↳ COR
HASKELL
              ↳ LetRed

mainModule Main
  ((splitAt :: Int  ->  [a ->  ([a],[a])) :: Int  ->  [a ->  ([a],[a]))

module Main where
  import qualified Prelude



Let/Where Reductions:
The bindings of the following Let/Where expression
(x : xs',xs'')
where 
vu42  = splitAt (n - 1) xs
xs'  = xs'0 vu42
xs''  = xs''0 vu42
xs''0 (vx,xs'') = xs''
xs'0 (xs',vy) = xs'

are unpacked to the following functions on top level
splitAt0Xs' xu xv = splitAt0Xs'0 xu xv (splitAt0Vu42 xu xv)

splitAt0Xs''0 xu xv (vx,xs'') = xs''

splitAt0Xs'' xu xv = splitAt0Xs''0 xu xv (splitAt0Vu42 xu xv)

splitAt0Xs'0 xu xv (xs',vy) = xs'

splitAt0Vu42 xu xv = splitAt (xu - 1) xv



↳ HASKELL
  ↳ LR
    ↳ HASKELL
      ↳ BR
        ↳ HASKELL
          ↳ COR
            ↳ HASKELL
              ↳ LetRed
HASKELL
                  ↳ NumRed

mainModule Main
  ((splitAt :: Int  ->  [a ->  ([a],[a])) :: Int  ->  [a ->  ([a],[a]))

module Main where
  import qualified Prelude



Num Reduction: All numbers are transformed to thier corresponding representation with Pos, Neg, Succ and Zero.

↳ HASKELL
  ↳ LR
    ↳ HASKELL
      ↳ BR
        ↳ HASKELL
          ↳ COR
            ↳ HASKELL
              ↳ LetRed
                ↳ HASKELL
                  ↳ NumRed
HASKELL
                      ↳ Narrow

mainModule Main
  (splitAt :: Int  ->  [a ->  ([a],[a]))

module Main where
  import qualified Prelude



Haskell To QDPs


↳ HASKELL
  ↳ LR
    ↳ HASKELL
      ↳ BR
        ↳ HASKELL
          ↳ COR
            ↳ HASKELL
              ↳ LetRed
                ↳ HASKELL
                  ↳ NumRed
                    ↳ HASKELL
                      ↳ Narrow
QDP
                          ↳ QDPSizeChangeProof

Q DP problem:
The TRS P consists of the following rules:

new_splitAt0Vu42(xw300, xw41, ba) → new_splitAt(new_primMinusNat(xw300), xw41, ba)
new_splitAt(Pos(Succ(xw300)), :(xw40, xw41), ba) → new_splitAt(new_primMinusNat(xw300), xw41, ba)
new_splitAt(Pos(Succ(xw300)), :(xw40, xw41), ba) → new_splitAt0Vu42(xw300, xw41, ba)

The TRS R consists of the following rules:

new_primMinusNat(Succ(xw3000)) → Pos(Succ(xw3000))
new_primMinusNat(Zero) → Pos(Zero)

The set Q consists of the following terms:

new_primMinusNat(Zero)
new_primMinusNat(Succ(x0))

We have to consider all minimal (P,Q,R)-chains.
By using the subterm criterion [20] together with the size-change analysis [32] we have proven that there are no infinite chains for this DP problem.

From the DPs we obtained the following set of size-change graphs: