MAYBE 1.305 H-Termination proof of /home/matraf/haskell/eval_FullyBlown_Fast/empty.hs
H-Termination of the given Haskell-Program with start terms could not be shown:



HASKELL
  ↳ BR

mainModule Main
  ((cycle :: [a ->  [a]) :: [a ->  [a])

module Main where
  import qualified Prelude



Replaced joker patterns by fresh variables and removed binding patterns.

↳ HASKELL
  ↳ BR
HASKELL
      ↳ COR

mainModule Main
  ((cycle :: [a ->  [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



↳ HASKELL
  ↳ BR
    ↳ HASKELL
      ↳ COR
HASKELL
          ↳ LetRed

mainModule Main
  ((cycle :: [a ->  [a]) :: [a ->  [a])

module Main where
  import qualified Prelude



Let/Where Reductions:
The bindings of the following Let/Where expression
xs'
where 
xs'  = xs ++ xs'

are unpacked to the following functions on top level
cycleXs' vx = vx ++ cycleXs' vx



↳ HASKELL
  ↳ BR
    ↳ HASKELL
      ↳ COR
        ↳ HASKELL
          ↳ LetRed
HASKELL
              ↳ Narrow
              ↳ Narrow

mainModule Main
  (cycle :: [a ->  [a])

module Main where
  import qualified Prelude



Haskell To QDPs


↳ HASKELL
  ↳ BR
    ↳ HASKELL
      ↳ COR
        ↳ HASKELL
          ↳ LetRed
            ↳ HASKELL
              ↳ Narrow
                ↳ AND
QDP
                    ↳ QDPSizeChangeProof
                  ↳ QDP
              ↳ Narrow

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

new_psPs(:(vy310, vy311), vy4, ba) → new_psPs(vy311, vy4, ba)

R is empty.
Q is empty.
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:



↳ HASKELL
  ↳ BR
    ↳ HASKELL
      ↳ COR
        ↳ HASKELL
          ↳ LetRed
            ↳ HASKELL
              ↳ Narrow
                ↳ AND
                  ↳ QDP
QDP
                    ↳ NonTerminationProof
              ↳ Narrow

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

new_cycleXs'(vy30, vy31, ba) → new_cycleXs'(vy30, vy31, ba)

R is empty.
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
We used the non-termination processor [17] to show that the DP problem is infinite.
Found a loop by semiunifying a rule from P directly.

The TRS P consists of the following rules:

new_cycleXs'(vy30, vy31, ba) → new_cycleXs'(vy30, vy31, ba)

The TRS R consists of the following rules:none


s = new_cycleXs'(vy30, vy31, ba) evaluates to t =new_cycleXs'(vy30, vy31, ba)

Thus s starts an infinite chain as s semiunifies with t with the following substitutions:




Rewriting sequence

The DP semiunifies directly so there is only one rewrite step from new_cycleXs'(vy30, vy31, ba) to new_cycleXs'(vy30, vy31, ba).




Haskell To QDPs