MAYBE 1.667 H-Termination proof of /home/matraf/haskell/eval_FullyBlown_Fast/Monad.hs
H-Termination of the given Haskell-Program with start terms could not be shown:



HASKELL
  ↳ LR

mainModule Monad
  ((foldM :: Monad b => (a  ->  c  ->  b a ->  a  ->  [c ->  b a) :: Monad b => (a  ->  c  ->  b a ->  a  ->  [c ->  b a)

module Monad where
  import qualified Maybe
import qualified Prelude

  foldM :: Monad c => (b  ->  a  ->  c b ->  b  ->  [a ->  c b
foldM a [] return a
foldM f a (x : xsf a x >>= (\fax ->foldM f fax xs)


module Maybe where
  import qualified Monad
import qualified Prelude



Lambda Reductions:
The following Lambda expression
\faxfoldM f fax xs

is transformed to
foldM0 f xs fax = foldM f fax xs



↳ HASKELL
  ↳ LR
HASKELL
      ↳ BR

mainModule Monad
  ((foldM :: Monad a => (c  ->  b  ->  a c ->  c  ->  [b ->  a c) :: Monad a => (c  ->  b  ->  a c ->  c  ->  [b ->  a c)

module Maybe where
  import qualified Monad
import qualified Prelude


module Monad where
  import qualified Maybe
import qualified Prelude

  foldM :: Monad b => (c  ->  a  ->  b c ->  c  ->  [a ->  b c
foldM a [] return a
foldM f a (x : xsf a x >>= foldM0 f xs

  
foldM0 f xs fax foldM f fax xs



Replaced joker patterns by fresh variables and removed binding patterns.

↳ HASKELL
  ↳ LR
    ↳ HASKELL
      ↳ BR
HASKELL
          ↳ COR

mainModule Monad
  ((foldM :: Monad a => (b  ->  c  ->  a b ->  b  ->  [c ->  a b) :: Monad a => (b  ->  c  ->  a b ->  b  ->  [c ->  a b)

module Monad where
  import qualified Maybe
import qualified Prelude

  foldM :: Monad b => (c  ->  a  ->  b c ->  c  ->  [a ->  b c
foldM vw a [] return a
foldM f a (x : xsf a x >>= foldM0 f xs

  
foldM0 f xs fax foldM f fax xs


module Maybe where
  import qualified Monad
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
  ↳ LR
    ↳ HASKELL
      ↳ BR
        ↳ HASKELL
          ↳ COR
HASKELL
              ↳ Narrow
              ↳ Narrow

mainModule Monad
  (foldM :: Monad b => (c  ->  a  ->  b c ->  c  ->  [a ->  b c)

module Maybe where
  import qualified Monad
import qualified Prelude


module Monad where
  import qualified Maybe
import qualified Prelude

  foldM :: Monad a => (b  ->  c  ->  a b ->  b  ->  [c ->  a b
foldM vw a [] return a
foldM f a (x : xsf a x >>= foldM0 f xs

  
foldM0 f xs fax foldM f fax xs



Haskell To QDPs


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

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

new_psPs(:(vz100, vz101), vz8, h) → new_psPs(vz101, vz8, h)

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
  ↳ LR
    ↳ HASKELL
      ↳ BR
        ↳ HASKELL
          ↳ COR
            ↳ HASKELL
              ↳ Narrow
                ↳ AND
                  ↳ QDP
QDP
                    ↳ DependencyGraphProof
              ↳ Narrow

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

new_foldM0(vz3, vz51, vz9, h, ba) → new_foldM(vz3, vz51, ty_IO, h, ba)
new_gtGtEs(vz3, vz51, h, ba) → new_foldM(vz3, vz51, ty_Maybe, h, ba)
new_gtGtEs0(vz3, vz51, h, ba) → new_foldM(vz3, vz51, ty_[], h, ba)
new_foldM(vz3, :(vz50, vz51), ty_IO, h, ba) → new_foldM(vz3, vz51, ty_IO, h, ba)
new_foldM(vz3, :(vz50, vz51), ty_[], h, ba) → new_gtGtEs0(vz3, vz51, h, ba)
new_foldM(vz3, :(vz50, vz51), ty_Maybe, h, ba) → new_gtGtEs(vz3, vz51, h, ba)
new_gtGtEs0(vz3, vz51, h, ba) → new_gtGtEs0(vz3, vz51, h, ba)

R is empty.
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
The approximation of the Dependency Graph [15,17,22] contains 3 SCCs with 1 less node.

↳ HASKELL
  ↳ LR
    ↳ HASKELL
      ↳ BR
        ↳ HASKELL
          ↳ COR
            ↳ HASKELL
              ↳ Narrow
                ↳ AND
                  ↳ QDP
                  ↳ QDP
                    ↳ DependencyGraphProof
                      ↳ AND
QDP
                          ↳ QDPSizeChangeProof
                        ↳ QDP
                        ↳ QDP
              ↳ Narrow

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

new_foldM(vz3, :(vz50, vz51), ty_IO, h, ba) → new_foldM(vz3, vz51, ty_IO, h, 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
  ↳ LR
    ↳ HASKELL
      ↳ BR
        ↳ HASKELL
          ↳ COR
            ↳ HASKELL
              ↳ Narrow
                ↳ AND
                  ↳ QDP
                  ↳ QDP
                    ↳ DependencyGraphProof
                      ↳ AND
                        ↳ QDP
QDP
                          ↳ UsableRulesReductionPairsProof
                        ↳ QDP
              ↳ Narrow

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

new_gtGtEs0(vz3, vz51, h, ba) → new_foldM(vz3, vz51, ty_[], h, ba)
new_foldM(vz3, :(vz50, vz51), ty_[], h, ba) → new_gtGtEs0(vz3, vz51, h, ba)
new_gtGtEs0(vz3, vz51, h, ba) → new_gtGtEs0(vz3, vz51, h, ba)

R is empty.
Q is empty.
We have to consider all minimal (P,Q,R)-chains.
By using the usable rules with reduction pair processor [15] with a polynomial ordering [25], all dependency pairs and the corresponding usable rules [17] can be oriented non-strictly. All non-usable rules are removed, and those dependency pairs and usable rules that have been oriented strictly or contain non-usable symbols in their left-hand side are removed as well.

The following dependency pairs can be deleted:

new_gtGtEs0(vz3, vz51, h, ba) → new_foldM(vz3, vz51, ty_[], h, ba)
new_foldM(vz3, :(vz50, vz51), ty_[], h, ba) → new_gtGtEs0(vz3, vz51, h, ba)
No rules are removed from R.

Used ordering: POLO with Polynomial interpretation [25]:

POL(:(x1, x2)) = 2 + x1 + 2·x2   
POL(new_foldM(x1, x2, x3, x4, x5)) = x1 + x2 + 2·x3 + x4 + x5   
POL(new_gtGtEs0(x1, x2, x3, x4)) = 1 + x1 + 2·x2 + x3 + x4   
POL(ty_[]) = 0   



↳ HASKELL
  ↳ LR
    ↳ HASKELL
      ↳ BR
        ↳ HASKELL
          ↳ COR
            ↳ HASKELL
              ↳ Narrow
                ↳ AND
                  ↳ QDP
                  ↳ QDP
                    ↳ DependencyGraphProof
                      ↳ AND
                        ↳ QDP
                        ↳ QDP
                          ↳ UsableRulesReductionPairsProof
QDP
                              ↳ NonTerminationProof
                        ↳ QDP
              ↳ Narrow

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

new_gtGtEs0(vz3, vz51, h, ba) → new_gtGtEs0(vz3, vz51, h, 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_gtGtEs0(vz3, vz51, h, ba) → new_gtGtEs0(vz3, vz51, h, ba)

The TRS R consists of the following rules:none


s = new_gtGtEs0(vz3, vz51, h, ba) evaluates to t =new_gtGtEs0(vz3, vz51, h, 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_gtGtEs0(vz3, vz51, h, ba) to new_gtGtEs0(vz3, vz51, h, ba).





↳ HASKELL
  ↳ LR
    ↳ HASKELL
      ↳ BR
        ↳ HASKELL
          ↳ COR
            ↳ HASKELL
              ↳ Narrow
                ↳ AND
                  ↳ QDP
                  ↳ QDP
                    ↳ DependencyGraphProof
                      ↳ AND
                        ↳ QDP
                        ↳ QDP
QDP
                          ↳ QDPSizeChangeProof
              ↳ Narrow

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

new_gtGtEs(vz3, vz51, h, ba) → new_foldM(vz3, vz51, ty_Maybe, h, ba)
new_foldM(vz3, :(vz50, vz51), ty_Maybe, h, ba) → new_gtGtEs(vz3, vz51, h, 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 To QDPs


↳ HASKELL
  ↳ LR
    ↳ HASKELL
      ↳ BR
        ↳ HASKELL
          ↳ COR
            ↳ HASKELL
              ↳ Narrow
              ↳ Narrow
QDP
                  ↳ DependencyGraphProof

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

new_foldM0(vz3, vz51, vz9, h, ba, []) → new_foldM(vz3, vz9, vz51, ty_IO, h, ba, [])
new_gtGtEs(Just(vz60), vz3, vz51, h, ba, []) → new_foldM(vz3, vz60, vz51, ty_Maybe, h, ba, [])

R is empty.
Q is empty.
We have to consider all (P,Q,R)-chains.
The approximation of the Dependency Graph [15,17,22] contains 0 SCCs with 2 less nodes.